Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction.
Mountains have helped (A) to protect the Swiss (B) from invaders, and indeed, Switzerland (C) has remained at peace while other European nations (D) engaging in war.
A. to protect
B. from invaders
C. has remained at peace
D. engaging in war
Đáp án : D
engaging in war => was engaging in war : đang tham gia vào chiến tranh
Đúng 0
Bình luận (0)