问题

Though he had failed twice, the strong-willed boy decided to make a third attempt_________ it[ ]

A:to
B:on
C:at
D:B &C

正确答案是：

同类题型

The problem is not ____ so easy as you think It’s far from being settled

He ___ go to work by bus, but now he ___ riding a bicycle to work.

He has been absent ________ class for quite a long time

The operation room in every hospital has to______ bacteria of any kind.

It’s.I think it’s very easy.