---Why does Maria look so tired?---She missed our school bus, ______she had to walk here all the way. 
#55611
A
or
B
so
C
but
D
and
推荐题目
I don’t know _____ or not he will come . _______ he comes , I will call you .
#55872
A
whether ; If
B
whether ; Whether
C
if ; If
D
if ; Whether
 --_______ will the meeting last? --_______ they reach an agreement.
#55956
A
How long; Not until
B
When; Not until
C
How long; Until
D
When; Until