The monument was built in honor of the explorer who was believed _____ the river.
| A．to have discovered | B．to have been discovered |
| C．to discover | D．having been discovered |
Don't __________ making mistakes. They are a naturalpart of learning.
| A．worries | B．worry about | C．be worried | D．be worried that |
All the、doctors in the hospital insisted that he __________ badly wounded and that he __________ at once.
| A．should be；be operated on |
| B．were;must be operated on |
| C．were；should be operated |
| D．was；be operated on |
__________，there are 50，000 visitors to the exhibitionevery day.
| A．At average | B．By average | C．On average | D．To average |
The custom, practice, idea and belief have __________ from generation to generation.
| A．passed down |
| B．been passed down |
| C．been carried forward |
| D．to passed on |
__________ meet her at the railway station, he had toget up early.
| A．In order that | B．In order to | C．So that | D．So as to |