diff --git a/data_juicer/ops/mapper/nlpaug_en_mapper.py b/data_juicer/ops/mapper/nlpaug_en_mapper.py
index 8509c1ba0..ae40b461c 100644
--- a/data_juicer/ops/mapper/nlpaug_en_mapper.py
+++ b/data_juicer/ops/mapper/nlpaug_en_mapper.py
@@ -118,22 +118,20 @@ def process(self, samples):
         texts_to_aug = samples[self.text_key][0]  # batch_size = 1
         res_samples = deepcopy(samples)
 
+        # get augmented texts
         if self.sequential:
             aug_texts = self.aug.augment(texts_to_aug, n=self.aug_num)
-            # add augmented samples to the batch with other replicate fields
-            for key in res_samples:
-                if key == self.text_key:
-                    res_samples[self.text_key] += aug_texts
-                else:
-                    res_samples[key] += res_samples[key] * len(aug_texts)
         else:
             # apply each aug method to generate several augmented texts
+            aug_texts = []
             for aug_method in self.aug:
-                aug_texts = aug_method.augment(texts_to_aug, n=self.aug_num)
-                res_samples[self.text_key] += aug_texts
-            # add other replicate fields
-            for key in res_samples:
-                if key != self.text_key:
-                    res_samples[key] = res_samples[key] * \
-                                       len(res_samples[self.text_key])
+                aug_texts += aug_method.augment(texts_to_aug, n=self.aug_num)
+
+        # add augmented samples to the batch with other replicate fields
+        res_samples[self.text_key] += aug_texts
+        # add other replicate fields
+        for key in res_samples:
+            if key != self.text_key:
+                res_samples[key] = res_samples[key] * \
+                                   len(res_samples[self.text_key])
         return res_samples
diff --git a/data_juicer/ops/mapper/nlpcda_zh_mapper.py b/data_juicer/ops/mapper/nlpcda_zh_mapper.py
index 51cf50e49..3f10b2f58 100644
--- a/data_juicer/ops/mapper/nlpcda_zh_mapper.py
+++ b/data_juicer/ops/mapper/nlpcda_zh_mapper.py
@@ -125,6 +125,7 @@ def process(self, samples):
         texts_to_aug = samples[self.text_key]
         res_samples = deepcopy(samples)
 
+        # get augmented texts
         if self.sequential:
             aug_texts = texts_to_aug
             for aug_method in self.aug_pipeline:
@@ -136,20 +137,17 @@ def process(self, samples):
                 aug_texts = results[:]
             if len(aug_texts) == 1 and aug_texts[0] == texts_to_aug[0]:
                 aug_texts = []
-            # add augmented samples to the batch with other replicate fields
-            for key in res_samples:
-                if key == self.text_key:
-                    res_samples[self.text_key] += aug_texts
-                else:
-                    res_samples[key] += res_samples[key] * len(aug_texts)
         else:
             # apply each aug method to generate several augmented texts
+            aug_texts = []
             for aug_method in self.aug_pipeline:
-                aug_texts = aug_method.replace(texts_to_aug[0])[1:]
-                res_samples[self.text_key] += aug_texts
-            # add other replicate fields
-            for key in res_samples:
-                if key != self.text_key:
-                    res_samples[key] = res_samples[key] * \
-                                       len(res_samples[self.text_key])
+                aug_texts += aug_method.replace(texts_to_aug[0])[1:]
+
+        # add augmented samples to the batch with other replicate fields
+        res_samples[self.text_key] += aug_texts
+        # add other replicate fields
+        for key in res_samples:
+            if key != self.text_key:
+                res_samples[key] = res_samples[key] * \
+                                   len(res_samples[self.text_key])
         return res_samples