The computer, help we human beings have stepped into the information age, should be regarded as one of the most important inventions in the 20th century.
| A．which | B．whose | C．with its | D．with whose |
My arrival was timed perfectly; it was the second weekend of November, when the world largest wine auction ________.
| A．held | B．was being held | C．was held | D．was to hold |
When McKie brings friends or volunteers to the area where she works, most of ________ spend the first day sobbing.
| A．them | B．whom | C．that | D．which |
_______ in the 1800s and first mass-produced in Germany, the harmonica(口琴) was designed to play simple folk tunes.
| A．Being invented | B．Inventing | C．Invented | D．Having invented |
The old scientist has been invited to a party ________ next Monday evening.
| A．holding | B．hold | C．being held | D．to be held |
As soon as she entered the room, the girl caught sight of the flowers ________ by her mother.
| A．buying | B．being bought | C．were bought | D．bought |