选C,
play tricks on sb.和某人搞恶作剧.You 'd better find __ the way to the 200.A.inB.outC.atD.onHe catches up the other students __ the help __ his teacher.A.with...of B.in...of C.with...and1. B. find out 经过努力找到....2. A. with the help of sb 在某人的帮助下希望能帮到你，祝更上一层楼O(∩_∩)O