diff --git a/safety-cedu-service/src/main/java/org/qinan/cedu/model/vo/PaperPageVO.java b/safety-cedu-service/src/main/java/org/qinan/cedu/model/vo/PaperPageVO.java
index 7f887a2a..6fc8fd02 100644
--- a/safety-cedu-service/src/main/java/org/qinan/cedu/model/vo/PaperPageVO.java
+++ b/safety-cedu-service/src/main/java/org/qinan/cedu/model/vo/PaperPageVO.java
@@ -1,5 +1,6 @@
 package org.qinan.cedu.model.vo;
 
+import com.fasterxml.jackson.annotation.JsonFormat;
 import io.swagger.annotations.ApiModel;
 import io.swagger.annotations.ApiModelProperty;
 import lombok.Data;
@@ -27,5 +28,6 @@ public class PaperPageVO {
     private BigDecimal paperPassScore;
 
     @ApiModelProperty("创建时间")
+    @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")
     private LocalDateTime createTime;
 }
diff --git a/safety-cedu-service/src/main/java/org/qinan/cedu/service/impl/PaperServiceImpl.java b/safety-cedu-service/src/main/java/org/qinan/cedu/service/impl/PaperServiceImpl.java
index 4fa06a29..85beaa4e 100644
--- a/safety-cedu-service/src/main/java/org/qinan/cedu/service/impl/PaperServiceImpl.java
+++ b/safety-cedu-service/src/main/java/org/qinan/cedu/service/impl/PaperServiceImpl.java
@@ -2,6 +2,7 @@ package org.qinan.cedu.service.impl;
 
 import cn.hutool.core.util.IdUtil;
 import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
+import com.baomidou.mybatisplus.core.conditions.update.LambdaUpdateWrapper;
 import com.baomidou.mybatisplus.core.metadata.IPage;
 import com.baomidou.mybatisplus.core.toolkit.Wrappers;
 import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
@@ -13,6 +14,8 @@ import org.qinan.cedu.convertor.PaperConvertor;
 import org.qinan.cedu.enums.DeleteEnum;
 import org.qinan.cedu.enums.PaperStatusEnum;
 import org.qinan.cedu.mapper.PaperMapper;
+import org.qinan.cedu.mapper.PaperQuestionRelMapper;
+import org.qinan.cedu.mapper.QuestionOptionMapper;
 import org.qinan.cedu.model.dto.PaperCopyDTO;
 import org.qinan.cedu.model.dto.PaperImportDTO;
 import org.qinan.cedu.model.dto.PaperPageQueryDTO;
@@ -23,9 +26,7 @@ import org.qinan.cedu.model.entity.QuestionDO;
 import org.qinan.cedu.model.entity.QuestionOptionDO;
 import org.qinan.cedu.model.vo.PaperImportVO;
 import org.qinan.cedu.model.vo.PaperPageVO;
-import org.qinan.cedu.service.PaperQuestionRelService;
 import org.qinan.cedu.service.PaperService;
-import org.qinan.cedu.service.QuestionOptionService;
 import org.qinan.cedu.service.support.QuestionExcelImporter;
 import org.qinan.safetyeval.infrastructure.support.InsertFieldDefaults;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -48,8 +49,8 @@ import java.util.stream.Collectors;
 @RequiredArgsConstructor
 public class PaperServiceImpl extends ServiceImpl<PaperMapper, PaperDO> implements PaperService {
 
-    private final PaperQuestionRelService paperQuestionRelService;
-    private final QuestionOptionService questionOptionService;
+    private final PaperQuestionRelMapper paperQuestionRelMapper;
+    private final QuestionOptionMapper questionOptionMapper;
     private final QuestionExcelImporter questionExcelImporter;
 
     @Autowired
@@ -109,10 +110,9 @@ public class PaperServiceImpl extends ServiceImpl<PaperMapper, PaperDO> implemen
         }
 
         // 查询源试卷绑定的试题及选项
-        List<PaperQuestionRelDO> rels = paperQuestionRelService.lambdaQuery()
+        List<PaperQuestionRelDO> rels = paperQuestionRelMapper.selectList(new LambdaQueryWrapper<PaperQuestionRelDO>()
                 .eq(PaperQuestionRelDO::getPaperId, source.getId())
-                .eq(PaperQuestionRelDO::getDeleteEnum, DeleteEnum.FALSE.getCode())
-                .list();
+                .eq(PaperQuestionRelDO::getDeleteEnum, DeleteEnum.FALSE.getCode()));
         List<Long> questionIds = rels.stream().map(PaperQuestionRelDO::getQuestionId).collect(Collectors.toList());
         List<QuestionDO> questions = questionIds.isEmpty() ? new ArrayList<>()
                 : Db.listByIds(questionIds, QuestionDO.class).stream()
@@ -120,10 +120,9 @@ public class PaperServiceImpl extends ServiceImpl<PaperMapper, PaperDO> implemen
                 .collect(Collectors.toList());
         List<Long> existQuestionIds = questions.stream().map(QuestionDO::getId).collect(Collectors.toList());
         List<QuestionOptionDO> allOptions = existQuestionIds.isEmpty() ? new ArrayList<>()
-                : questionOptionService.lambdaQuery()
+                : questionOptionMapper.selectList(new LambdaQueryWrapper<QuestionOptionDO>()
                 .in(QuestionOptionDO::getQuestionId, existQuestionIds)
-                .eq(QuestionOptionDO::getDeleteEnum, DeleteEnum.FALSE.getCode())
-                .list();
+                .eq(QuestionOptionDO::getDeleteEnum, DeleteEnum.FALSE.getCode()));
 
         // 新增试卷（使用请求中的名称/总分/合格分数）
         LocalDateTime now = LocalDateTime.now();
@@ -180,7 +179,7 @@ public class PaperServiceImpl extends ServiceImpl<PaperMapper, PaperDO> implemen
         }
         Db.saveBatch(questions);
         Db.saveBatch(newOptions);
-        paperQuestionRelService.saveBatch(newRels);
+        Db.saveBatch(newRels);
     }
 
     @Override
@@ -193,11 +192,10 @@ public class PaperServiceImpl extends ServiceImpl<PaperMapper, PaperDO> implemen
                 .eq(PaperDO::getDeleteEnum, DeleteEnum.FALSE.getCode())
                 .update();
         if (deleted) {
-            paperQuestionRelService.lambdaUpdate()
+            paperQuestionRelMapper.update(null, new LambdaUpdateWrapper<PaperQuestionRelDO>()
                     .set(PaperQuestionRelDO::getDeleteEnum, DeleteEnum.TRUE.getCode())
                     .set(PaperQuestionRelDO::getUpdateTime, LocalDateTime.now())
-                    .eq(PaperQuestionRelDO::getPaperId, id)
-                    .update();
+                    .eq(PaperQuestionRelDO::getPaperId, id));
         }
         return deleted;
     }
@@ -205,7 +203,7 @@ public class PaperServiceImpl extends ServiceImpl<PaperMapper, PaperDO> implemen
     @Override
     @Transactional(rollbackFor = Exception.class)
     public boolean bindQuestions(Long paperId, List<Long> questionIds) {
-        Db.remove(new LambdaQueryWrapper<PaperQuestionRelDO>()
+        paperQuestionRelMapper.delete(new LambdaQueryWrapper<PaperQuestionRelDO>()
                 .eq(PaperQuestionRelDO::getPaperId, paperId));
         if (CollectionUtils.isEmpty(questionIds)) {
             return true;
@@ -224,10 +222,9 @@ public class PaperServiceImpl extends ServiceImpl<PaperMapper, PaperDO> implemen
 
     @Override
     public List<Long> getQuestionIds(Long paperId) {
-        return paperQuestionRelService.lambdaQuery()
+        return paperQuestionRelMapper.selectList(new LambdaQueryWrapper<PaperQuestionRelDO>()
                 .eq(PaperQuestionRelDO::getPaperId, paperId)
-                .eq(PaperQuestionRelDO::getDeleteEnum, DeleteEnum.FALSE.getCode())
-                .list()
+                .eq(PaperQuestionRelDO::getDeleteEnum, DeleteEnum.FALSE.getCode()))
                 .stream()
                 .map(PaperQuestionRelDO::getQuestionId)
                 .collect(Collectors.toList());