求教两道语法单选题1.TheonlythingIcandonowis(go)onbymyself.请问这里为何要选go,不选going?2.Ifyouhavetime,you'dbetter(waiting)tillhecomesback.请问这里为何要选waiting,不选wait?

Question

求教两道语法单选题
1.The only thing I can do now is (go) on by myself.
请问这里为何要选go,不选going?
2.If you have time,you'd better (waiting) till he comes back.
请问这里为何要选waiting,不选wait?

Answer 1

1.The only thing I can do now is (go) on by myself.
这里的go省略了to,应该是The only thing I can do now is to go on by myself.“I can do”是插入语~
2.If you have time,you'd better (waiting) till he comes back.
这里的waiting应该是持续一个状态直到他回来,所以是进行时
应该是这样