The monument was built in honor of the explorer who was believed _____ the river.
| A．to discover | B．to have been discovered |
| C．to have discovered | D．having been discovered |
When the big bills for mother's hospital care came, father was glad he had money in the bank to _____.
| A．fall short of | B．fall through |
| C．fall back on | D．fall in with |
The farmers were more anxious for rain than the people in the city because they had more _____.
| A．at length | B．at last | C．at stake | D．at ease |
It is clear that the whole world is passing through a social revolution in which a central _____ must be taken by scientists and technologists.
| A．process | B．attention | C．measure | D．part |
The author of the report is well _____ with the problems in the hospital because he has been working there for many years.
| A．acquainted | B．informed | C．enlightened | D．advised |
With the change of the economic foundation the entire immense superstructure is _____ rapidly transformed.
| A．anything but | B．more or less | C．at large | D．any more |