1,I’ll call you before--(leave)
leaving （before介词.介词后+ 动词ing形式）
2,--(walk)on the moon is like--(jump)and--(fly)at the same time
Walking 动名词做主语
jumping,flying 用于like(像)的后面.like介词,道理同上.
3,--(lie) is wrong,You shouldn’t--(lie)again
Lying lying是lie的动名词,做主语.
lie shouldn't +_ 动原
4,--(swim)in the sea in summer is great fun
Swimming 动名词,做主语
5,she is very good at--(speak) fireign languages
speaking at 介词.介词后+ 动词ing形式
6,--(talk)loudly in the exhibition hall is not allowed
Talking 动名词,做主语
7,He really enjoys--(climb)mountains
climbing enjoy + doing
8,I feel like--(drink)some tea because I am thirsty
drinking feel like doing sth.想要做某事