I spend time as much as I could _____ the math problem.A.work out_其他解答

I spend time as much as I could _____ the math problem.
A.work out
B.to work out
C.working out
D.to work on

人气：186 ℃　时间：2019-09-22 02:55:37

解答

C
我尽可能地花时间来解决数学问题
这里的句型是spend time in doing sth
in 可以省略