There are 40 students in our class，who come from a ________of backgrounds.
| A．variety | B．mixture | C．extension | D．combination |
Michael __________ here to see you and he____________ a note on your desk.
| A．has come; had left | B．has been; has left |
| C．has come; left | D．has been; left |
I really wonder__________ he has posted me many parcels___________ we didn’t work together.
| A．that; before | B．which; since | C．X; when | D．that; since |
It is a rule in his family that __________ comes home earlier should cook the dinner for the family.
| A．anybody | B．who | C．who that | D．whoever |
The black horse is___________ of the pair.
| A．the strongest | B．the stronger |
| C．the strong | D．quite strong |
I coutdn't have got to the meeting on time____________ an earlier train.
| A．if I had not caught | B．unless I had caugh |
| C．if ! did not catch | D．unless I caugh |