---I think students should be allowed______ homework

问题补充：

---Ithinkstudentsshouldbeallowed ______homeworkwithfriends.---Idisagree.Theytalkinsteadof ______homework.A.do, doingB.to do, to doC.to do, doingD.doing, to do

答案：

C解析be allowed to do sth，表示被允许做某事，而instead of 为介词后街动词现在分词形式，故选C