12. The research is so designed that once ______ nothing can be done to change it.(A) begins 　　　　 (B

問題詳情

12. The research is so designed that once ______ nothing can be done to change it.
(A) begins 　　　　
(B) having begun　　
(C) beginning 　　　
(D) begun

答案：D
難度：困難0.275862
統計：A(75),B(35),C(79),D(72),E(0)

【Emily Lin】評論

once (the search is) begun

The research is so designed that once begun nothing can be done to change it. 這研究設計很好沒有什麼需要改的