Was it during the summer vacation ______ he went to Shanghai?
| A．that | B．when | C．where | D．which |
—It's a pity that Andrew didn't want to go to the conference.
—________ willing to go，we could have paid all his expenses.
| A．Had he been | B．Being |
| C．Was he | D．He had been |
The warning we were given as children ________ an apple a day keeps the doctor away may，in fact，have a scientific explanation.
| A．that | B．who | C．where | D．which |
WalMart，the world's largest retailer(零售商)，sells in three months ________ the numbertwo retailer Home Depot sells in a year.
| A．that | B．which | C．when | D．what |
Professor Tang didn't give us a speech today.It was ________ he had a traffic accident on the way to school.
| A．that | B．when | C．why | D．because |
He taught his father how to get to know ________ is going on in his university life on the Internet.
| A．how | B．that | C．what | D．which |