17000 bài tập tách từ đề thi thử môn Tiếng Anh có đáp án (Phần 3)

Only after she had finished the course did she realize she a wrong choice.

453/1620

Only after she had finished the course did she realize she _____________ a wrong choice.

had made

has made

had been making

was making

Giải thích

Chọn C