Many people can't learn any lessons from the mistakes they've made _____ they get hurt somehow.
#31589
A
whether
B
unless
C
if
D
as
推荐题目
_____there are many different types of food, some animals spend their lives eating only one type.
#30402
A
Since
B
As
C
Despite
D
While
—Did you return Fred’s call? —I didn’t need to ____ I’ll see him tomorrow.
#79824
A
though
B
unless
C
when
D
Because