题干

如图,已知AB∥CD,∠1=∠2,求证:AE∥DF.

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答案(点此获取答案解析)

证明:∵AB∥CD,

∴∠CDA=∠DAB,

∵∠1=∠2,

∴∠CDA﹣∠1=∠DAB﹣∠2,

∴∠FDA=∠DAE,

∴AE∥DF

同类题1

任务型阅读

    Are you planning to go to university? ____Perhaps you will be choosing the classes you want to take, finding accommodation and enrolling in other activities. However, if you go to university in Chile there is something extra you must do before you can begin.

    An essential part of starting university in Chile is the “mechoneo”____ Students beginning their first year at university are “welcomed” by the older university students. They are taken from their classrooms on an unknown day and blindfolded. The older students tear their clothes, cut their hair, and cover them in raw eggs and other disgusting things.

    ____ This will be based on how well the students do the activities, and many students try very hard as they want to be the king or queen of the year. The older students then take away everything of the younger students and tell them they must go out onto the street and ask people for money. They will need to bring back a certain amount of money in order to be given their things back.____

    During March it is common to see new university students all around town wearing ripped, dirty clothes and covered in paint and mess. But the “mechoneo” is increasingly a source of dispute and debate. Some students see it as an important tradition and a unique experience that help new arrivals get to know everyone.____ There have been campaigns to ban or soften it in favour of more “positive welcomes'', and student organizations in some universities have voted to end the “mechoneo” completely.

A. It is an ancient university tradition here.

B. The younger students are forced to do games in dirty places.

C. The “queen mechona” and “king mechon” are chosen that day.

D. They have to do games and take up challenges for a whole day.

E. But others find it abusive, like a form of bullying.

F. What do you think you need to do in the first few weeks?

G. The money is then used to have a massive welcome party at night-time.

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                                                                                              如何降盐不降味
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