Not a single mistake _______ in the last test.
| A．she made | B．made she | C．did she make | D．she did make |
The professor devoted all his life ____the treatment of AIDS．
A to research B．in researching C．to researching D．at researching
----Where did you put the broom,Tom?
-----I _______it behind the door．But now it is gone．
| A．do put | B．do putting | C．did to put | D．did put |
They experimented _____the new medicine _____anima
ls．
A．on; to B by ; on C．with ; on D with; to
Children under six are not ______to school except those of extraordinary intelligence．
A．permitted B．admitted C accepted D．received
three times，but she still couldn’t follow what the old man said．
| A．Having told | B．Having been told |
| C．She had been told | D．Though he had been told |