---I find the more we study, the more difficulty we have ________ out Maths problems.---Oh, I agree with you. Maths is more and more difficult.
#50150
A
worked
B
work
C
works
D
working
推荐题目
Be sure ________ and tell me what happens.
#49799
A
writing
B
wrote
C
writes
D
to write
I couldn’t wait _____ the box as soon as I received the gift.
#49148
A
to open
B
open
C
opening
D
for opening