He made another wonderful discovery, ________ of great importance to science．

A．which I think is

B．which I think it is

C．which I think it

D．I think which is

After living in Paris for fifty years, he returned to the small town ________ he grew up as a child．

A．which

B．where

C．that

D．when

The weather turned out to be very good, ________ we hadn’t expect．

A．what

B．which

C．that

D．it

In the dark street, there wasn’t a single person ________ she could turn for help．

A．that

B．who

C．from whom

D．to whom

She heard a terrible noise, ________ brought her heart into her mouth．

A．it

B．which

C．this

D．that

He paid the boy ＄10 for washing ten windows, most of ________ hadn’t been cleaned for at least a year．

A．these

B．those

C．that

D．which

All ________ is needed is a supply of oil．

A．the thing

B．that

C．what

D．which

His parents wouldn’t let him marry anyone ________ family was poor．

A．of whom

B．whom

C．of whose

D．whose

Finally the thief handed everything ________ he had stolen to the police．

A．which

B．what

C．whatever

D．that

Lincoln, ________ life was once hard, were elected President of American．

A．for whom

B．who

C．to whom

D．/