问题
Only when _____ to explain ____ the reason for this. [ ]
A: did he start; she realized
B: he started; did she realize
C: did he start; she had realized
D: he started; had she realized
B: he started; did she realize
C: did he start; she had realized
D: he started; had she realized
正确答案是：
同类题型
There _____ a football match this afternoon.
The talk show isn’t interesting at all. Very people like it.
Jeff _______ heavy and he ________ brown hair.
Beyond the lake _____ quantities of birds coming fromthe North every winter.
The little boy ________ in the mud all morning. No wonder he is dirty from head to foot. [ ]