They finally got lost. They then realized the importance of a map.
A. But for their awareness of the importance of a map, they could have got lost.
B. Hardly had they realized that a map was essential when they got lost.
C. Not until they realized the importance of a map did they get lost.
D. Only after they had got lost did they realize that a map was vital
Giải thích
D
Only after + mệnh đề + trợ V + S + V +....: Chỉ sau khi.....thì ai đó mới...
*Cấu trúc các câu còn lại
A: But for + N, S+ would/could + have + PII +.....: đảo ngữ câu điều kiện loại 3, diễn tả điều không thể xảy ra trong quá khứ.
B: Hardly had S PII when S V(quá khứ đơn): Ai đó vừa mới .... thì đã ....
C: Not until + Clause + trợ V + S + V: Chỉ đến khi....thì ai đó mới....
C. Not until they realized the importance of a map did they get lost.