30．—Peter looked tired and a little absent-minded at the meeting．
—He _____ up too late．
| A．may stay | B．could stay |
| C．should have stayed | D．must have stayed |
--Thank you very much.
--Not at all , I was____________ glad to help.
| A．too | B．only too | C．not so | D．much |
In Switzerland, six miles west of Geneva,___________ a collection of laboratory buildings.
| A．lie | B．are lying | C．lies | D．lays |
Collecting stamps as a hobby___________ increasingly popular during the past fifty years.
| A．becomes | B．became | C．has become | D．had become |
The train was__________ to arrive at 11:30,but was an hour late.
| A．about | B．likely | C．certain | D．supposed |
__________ full preparations, we decided to put off the meeting till next week.
| A．We did not make | B．Having not made |
| C．We had not made | D．Not having made |