John complained to the bookseller that there were several pages _______ in the dictionary.
| A．missing | B．losing | C．dropping | D．leaking |
Hardly____into the country____it began to rain.
| A．we had got;when | B．we got;than |
| C．had we got;when | D．did we get;than |
It is I____singing in the garden.
| A．who are | B．who is | C．that am | D．that is |
It was____the old worker came that we____the experiment.
| A．until;didn’t begin | B．not until;began |
| C．until;began | D．not until;didn’tbegin |
____be careful when crossing the street!
| A．Must | B．Should | C．Ought to | D．Do |
___come again.
| A．Do | B．Can | C．May | D．Did |