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笔筒中放有2支黑色和1支红色共3支签字笔,先从笔筒中随机取出一支笔,使用后放回笔筒,第二次再从笔筒中随机取出一支笔使用,则两次使用的都是黑色笔的概率为____.
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    For some people, choosing which sports to play throughout high school is hard because they have never really played an organized sport before and aren't sure what they'll enjoy most.____

    ____ If you're great at basketball but would rather play football because you think it's more fun, then give it a go (just make sure it's coot with morn and dad).

    Sports are meant to be fun.____ What's the worst that can happen? If you get cut, you can always try another sport. And sports like track don't typically cut participants from the team. You can still participate even if you're not in the team for the competition.

    Some sports, like basketball or baseball, require every person on the field to be working well together.____

    Sports like tennis, track and field, swimming, gymnastics, and wrestling are all sports where individual performances are tallied(计分)into team scores.____ However, for the most part it's possible to win a solo event in these sports and still have your team lose or vice-versa(反之亦然).

    No one knows you better than you do. Maybe you enjoy the spotlight. Maybe you get annoyed by the way teammates act. Luckily, there are many individualized sports to choose from.

A.Many people are attracted to team sports.

B.Besides swimming, try fishing, sailing, skiing, and surfing.

C.Of course there are exceptions, like relays in track and swimming.

D.For others it's tough because their friends don't like to play the same sports.

E.No matter what your problem is, you have to make the decision that is best for you.

F.If there is a sport you really enjoy but you aren't sure if you can make the team, try out anyway.

G.Sure, certain people perform much better than others, but superstars don't necessarily make a good team!