题目内容：

About six months,the letter they were looking forward
About six months,the letter they were looking forward to ___at last.
A.arrived.B.arriving
make oneself

优质解答

A.arrived这是谓语 动词
与定语从句they were looking forward to无关
make oneself done是使 自己 被 如何 是过去分词作宾补
如 he can't make himself understood 他不能使自己被理解