－How amazing it is that astronauts are exploring outer space!

－It’s a challenge, I guess, ________ man against nature．

A．of

B．for

C．by

D．about

－Why does the Lake smell terrible?

－Because large quantities of water ________．

A．have polluted

B．is being polluted

C．has been polluted

D．have been polluted

－Bruce, I really appreciate your handwriting．

－________．

A．I practice every day

B．Thank you very much

C．No, I don’t think so

D．Well, it’s not good enough

It is generally considered unwise to give a child ________ he or she wants．

A．however

B．whatever

C．whichever

D．whenever

Being a parent is not always easy, and being the parent of a child with special needs often carries with ________ extra stress．

A．it

B．them

C．one

D．him

________ twice, the postman refused to deliver our letters unless we chained our dog．

A．Being bitten

B．Bitten

C．Having bitten

D．To be bitten

The biggest whale is ________ blue whale,which grows to be about 29 meters long-the height of ________ 9-story building．

A．the; the

B．a; a

C．a; the

D．the; a

John was given the same suitcase his father and grandfather ________ with them to school．

A．took

B．had taken

C．were taking

D．would take

At first he hated the new job but decided to give himself a few months to see ________ It got any better．

A．when

B．how

C．why

D．if

When I talked with my grandma on the phone, she sounded weak, but by the time we ________ up, her voice had been full of life．

A．were hanging

B．had hung

C．hung

D．would hang