The news shocked the public,________ to great concern about students’ safety at school．
| A．having led | B．led | C．leading | D．to lead |
—What were you doing when she dropped in?
—I for a while and_________ some reading.
| A．was playing; was going to do | B．played; did |
| C．had played; was going to do | D．had played; did |
It was not a good idea to go skating. You __________your leg.
| A．can break | B．could break |
| C．could have broken | D．could have been broken |
Although motor car has been with us for almost a century, I have never been able to drive __________American one.
| A．the ; an | B．was remained | C．a; the | D．the ; the |
Nothing__________ after the terrible fire which had been caused by someone smoking in bed.
| A．left | B．was remained | C．remained | D．continued |
If you want to see a doctor, fix the date with him ahead of time. This is a common ___________ in the USA.
A. habit B. law C. rule D. custom