_______ on the top of the mountain is an ancient tower ______ back to two hundred years ago.
| A．Standing；dating |
| B．To stand；to date |
| C．Having stood；dating |
| D．Stand；dated |
When and where to build the new factory _____ yet.
| A．have not decided | B．are not decided |
| C．has not decided | D．is not decided |
I have many friends, ________ some are businessmen.
| A．of whom | B．from which | C．who of | D．of them |
School children must be taught how to deal with dangerous ________.
| A．states | B．conditions | C．situations | D．positions |
The survey shows that ______ of the population in the country ______ adults.
| A．three fifths; is | B．three fifths; are |
| C．three fifth; are | D．three fifth; is |
The workers do nothing but _______ tea and talk to each other.
| A．drinking | B．to drink | C．drink | D．are drinking |