Our visitors decided to stay in our city for _____ two days as they wanted to have a look around.

The Quality Control Staff is responsible _____ the quality of the products that come out of the factory.

（ ） some mammals came to live in the sea is now known.

I’m not used to （ ） in that impolite way.

The hotel was reasonably comfortable but the food lacked （ ） and the service was poor.

Jean did not have time to go to the concert last night because she was busy （ ） for her history examination.

Humble （ ） it may be, there is no place like home.

What time would it be convenient _____us to meet again?

Only when （ ） in the afternoon （ ） able to leave.

Mr. Phillips caught up with the boy in the corridor and （ ） his hand on his shoulder.

We could see the stars （ ） well from the top of the mountain.

Our teachers always tell us to believe in （ ） we do and who we are if we want to succeed.