—It’s necessary ____ our environment(环境). —I agree with you.
#50553
A
protect（保护）
B
protecting
C
to protect
D
protects
推荐题目
Although we’ve learned English for years, we have trouble _____ the foreigners.
#50181
A
understand
B
to understand
C
understanding
D
of understanding
It’s easy __________you to say sorry, but remember __________ be late again.
#50925
A
for; not to
B
for; don’t
C
of; not to
D
of; to
She hardly ever speaks English after class, for she is afraid mistakes.
#50275
A
to making
B
to make
C
of make
D
makes