問題詳情
2.6 The marine biologist ______ the long term memory of small whales.
(A) to investigate
(B) had been being investigate
(C) is being investigated
(D) has been investigating
參考答案
答案：D
難度：簡單0.636
書單：沒有書單，新增
用户評論
【有哥在】評論
一直持續在做（從過去到現在）適用『現在完...
【wooo】評論
現在進行完成式表過去到現在一直在進行中