--It’sdifficultforthevillagechildrentocrosstheriverfors...

問題詳情：

--It’s difficult for the village children to cross the river for school.

    --I think a bridge _______ over the river.

A. should be built        B. is being built     C. has been built          D. was built

【回答】

A

知識點：動詞語態

題型：選擇題