diff --git a/en/docs/chapter_backtracking/permutations_problem.md b/en/docs/chapter_backtracking/permutations_problem.md
index 9dc48b908..31ad05319 100644
--- a/en/docs/chapter_backtracking/permutations_problem.md
+++ b/en/docs/chapter_backtracking/permutations_problem.md
@@ -6,7 +6,7 @@ The table below lists several example data, including the input arrays and their
Table Permutation examples
-| Input array | Permutations |
+| Input array | Permutations |
| :---------- | :----------------------------------------------------------------- |
| $[1]$ | $[1]$ |
| $[1, 2]$ | $[1, 2], [2, 1]$ |
diff --git a/en/docs/chapter_stack_and_queue/deque.md b/en/docs/chapter_stack_and_queue/deque.md
index e49e249a4..5305071b6 100644
--- a/en/docs/chapter_stack_and_queue/deque.md
+++ b/en/docs/chapter_stack_and_queue/deque.md
@@ -10,14 +10,14 @@ The common operations in a double-ended queue are listed below, and the names of
Table Efficiency of double-ended queue operations
-| Method Name | Description | Time Complexity |
-| ------------- | --------------------------- | --------------- |
+| Method Name | Description | Time Complexity |
+| ------------- | -------------------------- | --------------- |
| `pushFirst()` | Add an element to the head | $O(1)$ |
-| `pushLast()` | Add an element to the tail | $O(1)$ |
-| `popFirst()` | Remove the first element | $O(1)$ |
-| `popLast()` | Remove the last element | $O(1)$ |
-| `peekFirst()` | Access the first element | $O(1)$ |
-| `peekLast()` | Access the last element | $O(1)$ |
+| `pushLast()` | Add an element to the tail | $O(1)$ |
+| `popFirst()` | Remove the first element | $O(1)$ |
+| `popLast()` | Remove the last element | $O(1)$ |
+| `peekFirst()` | Access the first element | $O(1)$ |
+| `peekLast()` | Access the last element | $O(1)$ |
Similarly, we can directly use the double-ended queue classes implemented in programming languages: