--- Shall we call a taxi?---- Ok, Let me ______ the phone number in Yellow Pages.
Ask John ______ here at 7 pm tomorrow.
The air in Beijing is getting much ______ now than a few years ago.
He has two pets. One is a dog, ______ is a cat.
— Will you stay for lunch?— Sorry, I ______. My brother is coming to see me.
I phoned you at six yesterday evening, ______ nobody answered.