問題詳情

4. According to the latest study of IUCN, over one-fourth of the plants on the earth ______ already been extinct and will never be seen again.

(A) has

(B) have

(C) having

(D) had

參考答案

答案：B

統計：A:2,B:8,C:0,D:1,E:0

難度：計算中