15000 bài tập tách từ đề thi thử môn Tiếng Anh có đáp án (Phần 53)

By the time human beings become fully aware of the importance of the ozone layer, it ______ seriously damaged. A. will be B. will have been C. is D. has been

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By the time human beings become fully aware of the importance of the ozone layer, it ______ seriously damaged.

will be

will have been

is

has been

Giải thích

Đáp án B

Dấu hiệu nhận biết thì hoàn thành “By the time…”