_______, when Marx was already _______, he found it was important to study the situation in Russia, so he began to learn Russian.
| A．In 1870s, in his fifties | B．In 1870s, in fifties |
| C．In the 1870s, in fifties | D．In the 1870s, in his fifties |
I would rather ______a good book than _______out to play this afternoon．It's too hot outside．
| A．to read , to go | B．reading, going |
| C．read, go | D．to read, going |
That happened _______ a Monday morning．
| A．at | B．in | C．for | D．on |
----They go to school early in the morning．
---_________________．
| A．So do Tom． | B．So Tom do． | C．So does Tom． | D．So Tom does． |
Mr. Brown _____ go to bed early, but now he ____going to bed early．
| A．used to, used to | B．used to, is used to |
| C．is used to, sued to | D．is used to, is used to |
You can’t put off ______ your homework．You must do it now．
| A．to do | B．do |
| C．to doing | D．doing |