Lawrence Craven, a doctor from the USA, is the author of several published reports, one of ________ introduced the idea in 1953 ________ aspirin could reduce the risk of heart attacks.
| A．them; when | B．which; that |
| C．what; that | D．which; when |
Mary went to the box office at lunch time, but all the tickets __________ out.
| A．would sell | B．had been sold | C．have been sold | D．was selling |
News came from the office __________ Wang Lin had been admitted to Beijing University.
| A．which | B．what | C．that | D．where |
Whenever I met her, __________ was very often, she greeted me with a sweet smile.
| A．who | B．which | C．when | D．since |
Peter was so excited __________ he received an invitation from his friend to visit them.
| A．where | B．that | C．why | D．when |
I have reached a point in my life __________ I am supposed to make decisions of my own.
| A．which | B．where | C．how | D．why |