28. Vitamin D helps our bodies make a special chemical, and this special chemical, _______, affects our brains, making us feel happy.
| A．in turn | B．in particular | C．in return | D．in short |
_______ she came for school late is that she missed the early bus.
| A． What | B．That | C．Which | D．Why |
The telephone rang but I didn’t hear it. I _______ asleep.
| A． must be | B．should be | C．ought to have been | D．must have been |
—________you like that latest type of car so much，why not buy it?
—Well，I can’t afford so expensive a car. It is worth 200,000 yuan.
| A．As if | B．Even if | C．Now that | D．In case |
His ability is never in doubt----the question is _______he is prepared to work hard.
| A． whether | B．if | C．that | D．where |
If he______ quietly as the doctor instructed，he would not suffer so much now.
| A．lies | B．lay | C．had lain | D．should lie |