Doctor Fang has devoted all her time to _______ the patients.
—We can’t be successful _______ we keep working hard.—I agree with you.
_____ you ______ your brother can join us. We want one of you.
The number of swimmers ______ getting larger and larger. Look, a number of students _____ swimming in this river.
—Why do you look so sleepy in class, John?—Sorry, sir. I _____ to watch a football match last night.
Look, the old man who is playing ______ guitar is _______ university teacher.