______ apple fell from the tree and hit him on ______ head.
| A．An; the | B．The; the | C．An; 不填 | D．The; 不填 |
Someone is ringing the doorbell. Go and see ___________.
| A．who is he | B．who he is | C．who is it | D．who it is |
One ought __________ for what one hasn’t done.
| A．not to be punished | B．to not be punished |
| C．to not punish | D．not be punished |
Luckily good things _________ here to save local wildlife.
| A．are doing | B．are being done |
| C．had been done | D．will do |
The earth became so violent that it was not clear_________ the shape would last or not.
| A．if | B．how | C．whether | D．why |
__________ she couldn’t understand was _________ fewer and fewer students showed interest in her lessons.
| A．What; why | B．That; what | C．What; because | D．Why; that |