What can we students do _____ the environment?
#50177
A
to protect
B
protected
C
protecting
D
protects
推荐题目
Our teacher often tells us ________ too much time watching TV.
#49379
A
don’t spend
B
not spend
C
not to spend
D
not spending
— Do you feel like ______ out for a walk ?— Sorry, I would like ____ at home.
#49394
A
to go; study
B
going ; studying
C
to go; to study
D
going ; to study
She’ll spend as much time as she can      to improve her spoken English. 
#48523
A
speak English
B
to speak English
C
speaking English
D
speaks English