单选题 正弦波振荡器产生自激振荡()。

A、 要求电路中要有正反馈
B、 要求放大器的电压增益小于反馈网络的衰减倍数
C、 要求反馈信号与原放大器输入信号反相
D、 一旦形成,可一直无条件延续下去,除非断电
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A、 Big Pinwheel 17:30—18:30
B、 Quiz Show 18:30—19:00
C、 Thirty-minute News 19:00—19:30
D、 Soap Opera 20:00—22:00
E、 Soccer Night 22:00—23:30

单选题 Lucy is a Japanese visitor. She likes shopping in the downtown.

A、 Green Hotel: Close to the airport, telephone, bath, and TV.
B、 Sun Hotel: European restaurant, coffee shop, facing the south and a blue sea.
C、 Changjiang Hotel: Japanese restaurant, night club, shops, in the city center.
D、 Jinsha Hotel: Swimming pool, shops and supermarkets, large garden with flowers.
E、 Great Wall Hotel: Table tennis room, bar, swimming pool and Chinese restaurant.

单选题 David likes swimming and his wife likes shopping. They also want to live in a place with lots of flowers.

A、 Green Hotel: Close to the airport, telephone, bath, and TV.
B、 Sun Hotel: European restaurant, coffee shop, facing the south and a blue sea.
C、 Changjiang Hotel: Japanese restaurant, night club, shops, in the city center.
D、 Jinsha Hotel: Swimming pool, shops and supermarkets, large garden with flowers.
E、 Great Wall Hotel: Table tennis room, bar, swimming pool and Chinese restaurant.

单选题 Alice is an eight-year-old girl. She likes watching children’s programs.

A、 Big Pinwheel 17:30—18:30
B、 Quiz Show 18:30—19:00
C、 Thirty-minute News 19:00—19:30
D、 Soap Opera 20:00—22:00
E、 Soccer Night 22:00—23:30

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A、 Green Hotel: Close to the airport, telephone, bath, and TV.
B、 Sun Hotel: European restaurant, coffee shop, facing the south and a blue sea.
C、 Changjiang Hotel: Japanese restaurant, night club, shops, in the city center.
D、 Jinsha Hotel: Swimming pool, shops and supermarkets, large garden with flowers.
E、 Great Wall Hotel: Table tennis room, bar, swimming pool and Chinese restaurant.

单选题 Henry is a sports lover. He is fond of watching football matches.

A、 Big Pinwheel 17:30—18:30
B、 Quiz Show 18:30—19:00
C、 Thirty-minute News 19:00—19:30
D、 Soap Opera 20:00—22:00
E、 Soccer Night 22:00—23:30

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A、 Big Pinwheel 17:30—18:30
B、 Quiz Show 18:30—19:00
C、 Thirty-minute News 19:00—19:30
D、 Soap Opera 20:00—22:00
E、 Soccer Night 22:00—23:30

单选题 Doreen is a full-time housewife. She is crazy about TV series.

A、 Big Pinwheel 17:30—18:30
B、 Quiz Show 18:30—19:00
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