Question

【题目】The maths problem is not easy enough ___________

A. work out B. work it out

C. to work out D. to work it out

Answer 1

【答案】C

【解析】句意：这道数学题不容易计算出来。not + adj. /adv.+ enough to do sth.意思是“不够……不足以……，”排除A,B；The maths problem既是句子的主语同时又是work out的逻辑宾语，因此就不能再用it作宾语， 故答案为C。