---Have you heard of Earth Day? --- Yes, We have only one Earth. We have no choice but ________ it.
#49067
A
protect
B
protected
C
protecting
D
to protect
推荐题目
---Why does Tommy look unhappy ? --- Because his teacher makes him _______ the classroom all by himself .
#50728
A
to clean
B
clean
C
cleans
D
cleaning
—You forgot______ off the lights? It’s still on.—But I remember _______them off before I went out of the room.
#49390
A
turning; to turn
B
to turn; turning
C
turning ; turning
D
to turn; to turn