Dr. Bethune ________ working in spite of cutting his hand during an operation.
— ______ did you visit the Great Wall? — Last Sunday.
Roast duck is one of _______ dishes in Beijing.
I’d like to go swimming with you, ______ I am too busy today.
I ______ in the hospital yesterday. I had to look after my sick mother.
— May I smoke here? — No, you ______ . This is a no-smoking room.