people could not transport them easily====could not -------
people could not transport them easily====could not -------
I was so busy that I could not play tennis is with them====
we could not move them 和we could not be moving them 区别
翻译I could not help taking photos of them
They could not take part in the meeting.= They_ _ _take part
we could not help___
could not skate at
I could not catch
could not help but
could not have done
could not wait to
She could not help___________out.