— Jim has gone to Britain to see a modern art exhibition. — Oh, really? Do you know when he       ? 

I didn’t see your sister at the meeting. If she _____, she would have met my brother.

—Sorry. I ________ to post the letter for you. —Never mind. ________ it myself after school. 

 ---- You shouldn’t have gone there alone last night.---- But I ______, because Xiao Wang went there, too.

For some time the expert __________ people of the health risks caused by passive smoking. He     says he won’t stop until all the smokers around him decide to quit smoking.