Mark the letter A, B, C, or D on your answer sheet to indicate the cor

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

If we _______ the plans carefully, we would not have had so many serious mistakes.

• A. A. study
• B. B. had studied
• C. C. studied
• D. D. were studying

Vế sau có would not have P2 => câu điều kiện loại 3 chỉ một điều kiện không thể xảy ra trong quá khứ.