diff --git a/hzims-service-api/safeproduct-api/src/main/java/com/hnac/hzims/safeproduct/constants/SafeProductConstant.java b/hzims-service-api/safeproduct-api/src/main/java/com/hnac/hzims/safeproduct/constants/SafeProductConstant.java
index bcfb2fb..3a4e9b9 100644
--- a/hzims-service-api/safeproduct-api/src/main/java/com/hnac/hzims/safeproduct/constants/SafeProductConstant.java
+++ b/hzims-service-api/safeproduct-api/src/main/java/com/hnac/hzims/safeproduct/constants/SafeProductConstant.java
@@ -13,6 +13,15 @@ public interface SafeProductConstant {
     int SUCCESS = 1;
     int FAILURE = 0;
 
+    /**
+     * 文件后缀
+     */
+    String DOCX_SUFFIX = ".docx";
+    String PDF_SUFFIX = ".pdf";
+
+    /**
+     * 培训管理
+     */
     int TRAIN_PLAN_HAS_TEST = 1;
     int TRAIN_PLAN_HAS_NO_TEST = 0;
 }
diff --git a/hzims-service-api/safeproduct-api/src/main/java/com/hnac/hzims/safeproduct/dto/CarMaintenanceConfirmationDTO.java b/hzims-service-api/safeproduct-api/src/main/java/com/hnac/hzims/safeproduct/dto/CarMaintenanceConfirmationDTO.java
index 9bfbcf7..13b943f 100644
--- a/hzims-service-api/safeproduct-api/src/main/java/com/hnac/hzims/safeproduct/dto/CarMaintenanceConfirmationDTO.java
+++ b/hzims-service-api/safeproduct-api/src/main/java/com/hnac/hzims/safeproduct/dto/CarMaintenanceConfirmationDTO.java
@@ -1,10 +1,12 @@
 package com.hnac.hzims.safeproduct.dto;
 
+import com.fasterxml.jackson.annotation.JsonFormat;
 import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
 import lombok.Data;
 
 import javax.validation.constraints.NotNull;
+import javax.validation.constraints.Size;
 import java.math.BigDecimal;
 import java.util.Date;
 
@@ -21,10 +23,12 @@ public class CarMaintenanceConfirmationDTO {
     private Long carMaintenanceId;
 
     @NotNull
+    @Size(max = 500, message = "车辆管理人意见长度不能超过500")
     @ApiModelProperty("车辆管理人意见")
     private String managerAdvice;
 
     @NotNull
+    @JsonFormat(pattern = "yyyy-MM-dd")
     @ApiModelProperty("下次维保时间")
     private Date maintenanceNextTime;
 
diff --git a/hzims-service-api/safeproduct-api/src/main/java/com/hnac/hzims/safeproduct/entity/CarCheckItemEntity.java b/hzims-service-api/safeproduct-api/src/main/java/com/hnac/hzims/safeproduct/entity/CarCheckItemEntity.java
index 3461c52..cd02dc3 100644
--- a/hzims-service-api/safeproduct-api/src/main/java/com/hnac/hzims/safeproduct/entity/CarCheckItemEntity.java
+++ b/hzims-service-api/safeproduct-api/src/main/java/com/hnac/hzims/safeproduct/entity/CarCheckItemEntity.java
@@ -1,6 +1,5 @@
 package com.hnac.hzims.safeproduct.entity;
 
-import com.baomidou.mybatisplus.annotation.TableField;
 import com.baomidou.mybatisplus.annotation.TableName;
 import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
diff --git a/hzims-service-api/safeproduct-api/src/main/java/com/hnac/hzims/safeproduct/vo/CarCheckRecordDetailVO.java b/hzims-service-api/safeproduct-api/src/main/java/com/hnac/hzims/safeproduct/vo/CarCheckRecordDetailVO.java
index 2c1ff91..4aa745b 100644
--- a/hzims-service-api/safeproduct-api/src/main/java/com/hnac/hzims/safeproduct/vo/CarCheckRecordDetailVO.java
+++ b/hzims-service-api/safeproduct-api/src/main/java/com/hnac/hzims/safeproduct/vo/CarCheckRecordDetailVO.java
@@ -6,6 +6,7 @@ import io.swagger.annotations.ApiModelProperty;
 import lombok.Data;
 
 import java.math.BigDecimal;
+import java.util.Date;
 import java.util.List;
 
 /**
@@ -19,6 +20,9 @@ public class CarCheckRecordDetailVO {
     @ApiModelProperty("检查人")
     private String checker;
 
+    @ApiModelProperty("检查时间")
+    private Date checkTime;
+
     @ApiModelProperty("品牌")
     private String carBrand;
 
diff --git a/hzims-service-api/safeproduct-api/src/main/java/com/hnac/hzims/safeproduct/vo/CarUsedRecordDetailVO.java b/hzims-service-api/safeproduct-api/src/main/java/com/hnac/hzims/safeproduct/vo/CarUsedRecordDetailVO.java
index 06cdf91..b415ff1 100644
--- a/hzims-service-api/safeproduct-api/src/main/java/com/hnac/hzims/safeproduct/vo/CarUsedRecordDetailVO.java
+++ b/hzims-service-api/safeproduct-api/src/main/java/com/hnac/hzims/safeproduct/vo/CarUsedRecordDetailVO.java
@@ -27,6 +27,9 @@ public class CarUsedRecordDetailVO {
     @ApiModelProperty("品牌")
     private String carBrand;
 
+    @ApiModelProperty("车辆类型")
+    private String carType;
+
     @ApiModelProperty("车牌号")
     private String plateNumber;
 
diff --git a/hzims-service/safeproduct/src/main/java/com/hnac/hzims/safeproduct/mapper/CarUsedRecordMapper.xml b/hzims-service/safeproduct/src/main/java/com/hnac/hzims/safeproduct/mapper/CarUsedRecordMapper.xml
index 0150cb2..ad456ed 100644
--- a/hzims-service/safeproduct/src/main/java/com/hnac/hzims/safeproduct/mapper/CarUsedRecordMapper.xml
+++ b/hzims-service/safeproduct/src/main/java/com/hnac/hzims/safeproduct/mapper/CarUsedRecordMapper.xml
@@ -5,7 +5,7 @@
     <select id="getCarUsedRecord" resultType="com.hnac.hzims.safeproduct.vo.CarUsedRecordDetailVO">
         SELECT
             t1.code, t1.start_time, t1.used_location, t1.remark, t1.unit, t1.start_miles, t1.end_miles, t1.miles,
-            t1.img_path, t1.user, t1.end_time, t1.confirmation_time, t2.manager, t2.car_brand, t2.plate_number
+            t1.img_path, t1.user, t1.end_time, t1.confirmation_time, t2.manager, t2.car_brand, t2.car_type, t2.plate_number
         FROM
             hzims_car_used_record t1
             LEFT JOIN hzims_car t2 ON t1.car_id = t2.id
diff --git a/hzims-service/safeproduct/src/main/java/com/hnac/hzims/safeproduct/service/impl/CarCheckRecordServiceImpl.java b/hzims-service/safeproduct/src/main/java/com/hnac/hzims/safeproduct/service/impl/CarCheckRecordServiceImpl.java
index be47b72..1b55389 100644
--- a/hzims-service/safeproduct/src/main/java/com/hnac/hzims/safeproduct/service/impl/CarCheckRecordServiceImpl.java
+++ b/hzims-service/safeproduct/src/main/java/com/hnac/hzims/safeproduct/service/impl/CarCheckRecordServiceImpl.java
@@ -6,6 +6,7 @@ import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
 import com.baomidou.mybatisplus.core.metadata.IPage;
 import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
 import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
+import com.hnac.hzims.safeproduct.constants.SafeProductConstant;
 import com.hnac.hzims.safeproduct.dto.CarCheckRecordDTO;
 import com.hnac.hzims.safeproduct.entity.CarCheckItemEntity;
 import com.hnac.hzims.safeproduct.entity.CarCheckRecordEntity;
@@ -87,6 +88,7 @@ public class CarCheckRecordServiceImpl extends ServiceImpl<CarCheckRecordMapper,
             CarCheckRecordDetailVO carCheckRecordDetailVO = new CarCheckRecordDetailVO();
             // 车检记录属性
             carCheckRecordDetailVO.setCode(carCheckRecord.getCode());
+            carCheckRecordDetailVO.setCheckTime(carCheckRecord.getCheckTime());
             carCheckRecordDetailVO.setChecker(carCheckRecord.getChecker());
             carCheckRecordDetailVO.setConclusion(carCheckRecord.getConclusion());
             carCheckRecordDetailVO.setRemark(carCheckRecord.getRemark());
@@ -187,11 +189,11 @@ public class CarCheckRecordServiceImpl extends ServiceImpl<CarCheckRecordMapper,
      */
     @Override
     public void exportCarCheckRecordData(Long id, HttpServletResponse response) {
-        CarCheckRecordEntity carCheckRecordEntity = this.getById(id);
-        Map<String, Object> params = BaseUtil.obj2Map(carCheckRecordEntity);
-        String templateFile = "template/车检记录单.docx";
-        String wordPath = savePath + "/车检记录单.docx";
-        String pdfPath = savePath + "/车检记录单.pdf";
+        CarCheckRecordDetailVO carCheckRecordDetailVO = this.getCarCheckRecord(id);
+        Map<String, Object> params = BaseUtil.obj2Map(carCheckRecordDetailVO);
+        String templateFile = "template/车检记录单" + SafeProductConstant.DOCX_SUFFIX;
+        String wordPath = savePath + "/车检记录单" + SafeProductConstant.DOCX_SUFFIX;
+        String pdfPath = savePath + "/车检记录单" + SafeProductConstant.PDF_SUFFIX;
         BaseUtil.exportDocument(templateFile, params, wordPath, pdfPath, response);
     }
 
diff --git a/hzims-service/safeproduct/src/main/java/com/hnac/hzims/safeproduct/service/impl/CarMaintenanceServiceImpl.java b/hzims-service/safeproduct/src/main/java/com/hnac/hzims/safeproduct/service/impl/CarMaintenanceServiceImpl.java
index 9b7b1cc..30deedc 100644
--- a/hzims-service/safeproduct/src/main/java/com/hnac/hzims/safeproduct/service/impl/CarMaintenanceServiceImpl.java
+++ b/hzims-service/safeproduct/src/main/java/com/hnac/hzims/safeproduct/service/impl/CarMaintenanceServiceImpl.java
@@ -6,6 +6,7 @@ import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
 import com.baomidou.mybatisplus.core.metadata.IPage;
 import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
 import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
+import com.hnac.hzims.safeproduct.constants.SafeProductConstant;
 import com.hnac.hzims.safeproduct.dto.CarMaintenanceConfirmationDTO;
 import com.hnac.hzims.safeproduct.entity.CarEntity;
 import com.hnac.hzims.safeproduct.entity.CarMaintenanceEntity;
@@ -111,11 +112,11 @@ public class CarMaintenanceServiceImpl extends ServiceImpl<CarMaintenanceMapper,
      */
     @Override
     public void exportCarMaintenanceData(Long id, HttpServletResponse response) {
-        CarMaintenanceEntity carMaintenanceEntity = this.getById(id);
-        Map<String, Object> params = BaseUtil.obj2Map(carMaintenanceEntity);
-        String templateFile = "template/车辆维保记录单.docx";
-        String wordPath = savePath + "/车辆维保记录单.docx";
-        String pdfPath = savePath + "/车辆维保记录单.pdf";
+        CarMaintenanceDetailVO carMaintenanceDetailVO = this.getCarMaintenance(id);
+        Map<String, Object> params = BaseUtil.obj2Map(carMaintenanceDetailVO);
+        String templateFile = "template/车辆维保记录单" + SafeProductConstant.DOCX_SUFFIX;
+        String wordPath = savePath + "/车辆维保记录单" + SafeProductConstant.DOCX_SUFFIX;
+        String pdfPath = savePath + "/车辆维保记录单" + SafeProductConstant.PDF_SUFFIX;
         BaseUtil.exportDocument(templateFile, params, wordPath, pdfPath, response);
     }
 
diff --git a/hzims-service/safeproduct/src/main/java/com/hnac/hzims/safeproduct/service/impl/CarUsedRecordServiceImpl.java b/hzims-service/safeproduct/src/main/java/com/hnac/hzims/safeproduct/service/impl/CarUsedRecordServiceImpl.java
index 216e319..90f9977 100644
--- a/hzims-service/safeproduct/src/main/java/com/hnac/hzims/safeproduct/service/impl/CarUsedRecordServiceImpl.java
+++ b/hzims-service/safeproduct/src/main/java/com/hnac/hzims/safeproduct/service/impl/CarUsedRecordServiceImpl.java
@@ -6,16 +6,15 @@ import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
 import com.baomidou.mybatisplus.core.metadata.IPage;
 import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
 import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
+import com.hnac.hzims.safeproduct.constants.SafeProductConstant;
 import com.hnac.hzims.safeproduct.dto.CarUsedRecordConfirmationDTO;
 import com.hnac.hzims.safeproduct.entity.CarUsedRecordEntity;
 import com.hnac.hzims.safeproduct.enums.CarUsedRecordEnum;
 import com.hnac.hzims.safeproduct.mapper.CarUsedRecordMapper;
 import com.hnac.hzims.safeproduct.service.ICarUsedRecordService;
-import com.hnac.hzims.safeproduct.utils.AsposeUtil;
 import com.hnac.hzims.safeproduct.utils.BaseUtil;
 import com.hnac.hzims.safeproduct.vo.CarUsedRecordDetailVO;
 import com.hnac.hzims.safeproduct.vo.CarUsedRecordPageVO;
-import org.apache.poi.xwpf.usermodel.XWPFDocument;
 import org.springblade.core.mp.support.Query;
 import org.springblade.core.tool.api.R;
 import org.springblade.core.tool.utils.DateUtil;
@@ -24,7 +23,6 @@ import org.springframework.stereotype.Service;
 
 import javax.servlet.http.HttpServletResponse;
 import java.math.BigDecimal;
-import java.util.ArrayList;
 import java.util.Date;
 import java.util.List;
 import java.util.Map;
@@ -111,11 +109,11 @@ public class CarUsedRecordServiceImpl extends ServiceImpl<CarUsedRecordMapper, C
      */
     @Override
     public void exportCarUsedRecordData(Long id, HttpServletResponse response) {
-        CarUsedRecordEntity carUsedRecordEntity = this.getById(id);
-        Map<String, Object> params = BaseUtil.obj2Map(carUsedRecordEntity);
-        String templateFile = "template/用车记录单.docx";
-        String wordPath = savePath + "/用车记录单.docx";
-        String pdfPath = savePath + "/用车记录单.pdf";
+        CarUsedRecordDetailVO carUsedRecordDetailVO = this.getCarUsedRecord(id);
+        Map<String, Object> params = BaseUtil.obj2Map(carUsedRecordDetailVO);
+        String templateFile = "template/用车记录单" + SafeProductConstant.DOCX_SUFFIX;
+        String wordPath = savePath + "/用车记录单" + SafeProductConstant.DOCX_SUFFIX;
+        String pdfPath = savePath + "/用车记录单" + SafeProductConstant.PDF_SUFFIX;
         BaseUtil.exportDocument(templateFile, params, wordPath, pdfPath, response);
     }
 
diff --git a/hzims-service/safeproduct/src/main/java/com/hnac/hzims/safeproduct/utils/BaseUtil.java b/hzims-service/safeproduct/src/main/java/com/hnac/hzims/safeproduct/utils/BaseUtil.java
index 2f26680..ab862ed 100644
--- a/hzims-service/safeproduct/src/main/java/com/hnac/hzims/safeproduct/utils/BaseUtil.java
+++ b/hzims-service/safeproduct/src/main/java/com/hnac/hzims/safeproduct/utils/BaseUtil.java
@@ -55,7 +55,28 @@ public class BaseUtil {
     }
 
     /**
-     * 文件导出
+     * pdf文件导出
+     * @param templateFile 模板文件路径
+     * @param params 数据参数
+     * @param wordPath 文件生成路径
+     * @param pdfPath pdf生成路径
+     * @param response 响应类
+     */
+    public static void exportDocument(String templateFile, Map<String, Object> params, String wordPath, String pdfPath, HttpServletResponse response) {
+        try {
+            List<XWPFDocument> res = new ArrayList<>();
+            XWPFDocument document = BaseUtil.fillDocument(templateFile, params);
+            res.add(document);
+            BaseUtil.exportWord(res, wordPath);
+        } catch (Exception e) {
+            log.error("文件导出异常: {}", e.getMessage());
+        }
+        AsposeUtil.wordToPdf(wordPath, pdfPath);
+        BaseUtil.readPdf(response,pdfPath);
+    }
+
+    /**
+     * word文件导出
      * @param documents doc文件
      * @param savePath 存储路径
      */
@@ -67,22 +88,22 @@ public class BaseUtil {
                 document.write(out);
             }
         } catch (IOException e) {
-            log.error("文件导出异常: {}", e.getMessage());
+            log.error("word文件导出异常: {}", e.getMessage());
         }  finally {
             if (out != null) {
                 try {
                     out.close();
                 } catch (IOException e) {
-                    log.error("文件导出-输出流关闭异常: {}", e.getMessage());
+                    log.error("word文件导出-输出流关闭异常: {}", e.getMessage());
                 }
             }
         }
     }
 
     /**
-     * 数据写入模板文件
-     * @param templatePath 模板路径
-     * @param params 数据
+     * 数据写入
+     * @param templatePath 模板文件路径
+     * @param params 数据参数
      */
     public static XWPFDocument fillDocument(String templatePath, Map<String, Object> params) {
         XWPFDocument xwpfDocument = null;
@@ -113,7 +134,7 @@ public class BaseUtil {
                     "inline; filename= " + URLEncoder.encode(file.getName(), "UTF-8"));
             outputStream.flush();
         } catch (IOException e) {
-            e.printStackTrace();
+            log.error("本地pdf文件读取异常: {}", e.getMessage());
         } finally {
             try {
                 if (fileInputStream != null) {
@@ -128,16 +149,21 @@ public class BaseUtil {
         }
     }
 
+    /**
+     * 对象转map
+     * @param obj 对象类
+     * @return map参数
+     */
     public static Map<String, Object> obj2Map(Object obj) {
-        if(ObjectUtil.isNotEmpty(obj) && null != obj.getClass()) {
+        if (ObjectUtil.isNotEmpty(obj) && null != obj.getClass()) {
             Map<String, Object> result = new HashMap<>();
             List<Field> fieldList = new ArrayList<>();
             Class<?> clazz = obj.getClass();
-            while(clazz != null) {
+            while (clazz != null) {
                 fieldList.addAll(Arrays.asList(clazz.getDeclaredFields()));
                 clazz = clazz.getSuperclass();
             }
-            fieldList.forEach(field -> {
+            fieldList.forEach (field -> {
                 field.setAccessible(true);
                 Object value;
                 try {
@@ -145,11 +171,11 @@ public class BaseUtil {
                 } catch (IllegalAccessException e) {
                     throw new ServiceException("获取属性性出错");
                 }
-                if(value instanceof List) {
+                if (value instanceof List) {
                     List<Map<String, Object>> list = ((List<?>) value).stream().map(BaseUtil::obj2Map).collect(Collectors.toList());
                     result.put(field.getName(),list);
                 }
-                else if(value instanceof LocalDateTime) {
+                else if (value instanceof LocalDateTime) {
                     DateTimeToMap dateTimeToMap = field.getAnnotation(DateTimeToMap.class);
                     LocalDateTime time = (LocalDateTime) value;
                     if(ObjectUtil.isEmpty(dateTimeToMap)) {
@@ -159,10 +185,10 @@ public class BaseUtil {
                         result.putAll(LocalDateConvertMap(time,dateTimeToMap.prefix(),dateTimeToMap.split()));
                     }
                 }
-                else if(value instanceof Date) {
+                else if (value instanceof Date) {
                     DateTimeToMap dateTimeToMap = field.getAnnotation(DateTimeToMap.class);
                     Date time = (Date) value;
-                    if(ObjectUtil.isEmpty(dateTimeToMap)) {
+                    if (ObjectUtil.isEmpty(dateTimeToMap)) {
                         result.put(field.getName(),DateUtil.format(time,DateUtil.PATTERN_DATETIME));
                     }
                     else {
@@ -191,7 +217,7 @@ public class BaseUtil {
      * @return map对象
      */
     public static Map<String, Object> LocalDateConvertMap(LocalDateTime dateTime,String prefix,String split) {
-        HashMap<String, Object> result = new HashMap<String, Object>() {{
+        return new HashMap<String, Object>() {{
             put(prefix + split + "year", dateTime.getYear());
             put(prefix + split + "month", dateTime.getMonthValue());
             put(prefix + split + "day", dateTime.getDayOfMonth());
@@ -199,19 +225,5 @@ public class BaseUtil {
             put(prefix + split + "minuter", dateTime.getMinute());
             put(prefix + split + "second", dateTime.getSecond());
         }};
-        return result;
-    }
-
-    public static void exportDocument(String templateFile, Map<String, Object> params, String wordPath, String pdfPath, HttpServletResponse response) {
-        try {
-            List<XWPFDocument> res = new ArrayList<>();
-            XWPFDocument document = BaseUtil.fillDocument(templateFile, params);
-            res.add(document);
-            BaseUtil.exportWord(res, wordPath);
-        } catch (Exception e) {
-            throw new RuntimeException(e);
-        }
-        AsposeUtil.wordToPdf(wordPath, pdfPath);
-        BaseUtil.readPdf(response,pdfPath);
     }
 }
diff --git a/hzims-service/safeproduct/src/main/resources/db/1.0.1.sql b/hzims-service/safeproduct/src/main/resources/db/1.0.1.sql
index ef3b5b4..404ba74 100644
--- a/hzims-service/safeproduct/src/main/resources/db/1.0.1.sql
+++ b/hzims-service/safeproduct/src/main/resources/db/1.0.1.sql
@@ -197,6 +197,7 @@ CREATE TABLE `hzims_hygiene_plan` (
 CREATE TABLE `hzims_hygiene_zone` (
     `id` bigint(20) NOT NULL COMMENT '主键id',
     `hygiene_plan_id` bigint(20) NOT NULL COMMENT '卫生自查计划id',
+    `unit` varchar(50) NOT NULL COMMENT '单位',
     `zone` varchar(50) NOT NULL COMMENT '责任区',
     `principal` varchar(20) NOT NULL COMMENT '责任人',
     `check_item` mediumtext NOT NULL COMMENT '检查项',
@@ -269,8 +270,8 @@ CREATE TABLE `hzims_car_maintenance` (
     `code` varchar(50) NOT NULL COMMENT '编号',
     `maintenance_type` varchar(50) NOT NULL COMMENT '维保类型',
     `content` mediumtext NOT NULL COMMENT '维保内容',
-    `start_time` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP COMMENT '维保开始时间',
-    `end_time` datetime NOT NULL DEFAULT CURRENT_TIMESTAMP COMMENT '维保结束时间',
+    `start_time` date NOT NULL DEFAULT CURRENT_TIMESTAMP COMMENT '维保开始时间',
+    `end_time` date NOT NULL DEFAULT CURRENT_TIMESTAMP COMMENT '维保结束时间',
     `location` varchar(255) NOT NULL COMMENT '维保地点',
     `cost` bigint(20) NOT NULL COMMENT '维保费用',
     `maintainer` varchar(20) NOT NULL COMMENT '维保人',
diff --git a/hzims-service/safeproduct/src/main/resources/template/用车记录单.docx b/hzims-service/safeproduct/src/main/resources/template/用车记录单.docx
new file mode 100644
index 0000000..b1def9c
Binary files /dev/null and b/hzims-service/safeproduct/src/main/resources/template/用车记录单.docx differ
diff --git a/hzims-service/safeproduct/src/main/resources/template/车辆检查表.docx b/hzims-service/safeproduct/src/main/resources/template/车辆检查表.docx
new file mode 100644
index 0000000..683e1ef
Binary files /dev/null and b/hzims-service/safeproduct/src/main/resources/template/车辆检查表.docx differ