—People find it hard to get across the river—I think at least two bridgesover it．A. needB

—People find it hard to get across the river．
—I think at least two bridges over it．
A. need
B. are needing
C. will need
D. should be needed

A. needB. are needingC. will need(答案→)D. should be needed解析：本题的含义是在河上至少需要两座桥，本题桥在从句作主语，是动作的承受者，故被动结构，结构为be+过去分词，need的过去分词是needed，故选D。

我也是这个答案

哦，回答的不错

(答案→)不设统一答案。 解析：只要设计合理，文通句顺，书写认真即可。