Steel and iron can be used ______ bridges as well as machines.
| A．to make | B．to making | C．make | D．making |
Children are always ______, and usually think differently from adults.
| A．satisfied | B．social | C．untrue | D．creative |
I’m sure you ______ to us just now, because we already know the truth.
| A．lay | B．laid | C．lie | D．lied |
I have many friends, __________some are businessmen。
A of them B of whose C of which D of whom
He had been ill for a long time and _________ he was left behind in his work。
| A．however | B．consequently | C．otherwise | D．but |