—How many students are there in your school?
—_______ students, I think.
| A．Thousand of | B．Three thousands |
| C．Three thousand | D．Three thousands of |
_____ a good time we had yesterday!
| A．Where | B．How | C．What | D．Why |
When winter comes, days get _____ .
| A．long and long | B．longer and longer |
| C．shorter and shorter | D．short and short |
_____ of the two books are very interesting, so I can't decide which one to choose.
| A．All | B．Both | C．Either | D．Any |
Listen! Someone_____ singing in the next room.
| A．is | B．are | C．does | D．do |
The more you smile, the _____ you will feel.
| A．happy | B．happily | C．happier | D．more happily |