题干

下列有关光学器件的说法正确的是(  )

A:潜望镜是利用平面镜对光的反射原理制成的

B:凸透镜对光线起会聚作用,所以经过凸透镜折射的光一定是会聚光

C:放大镜成的像一定是正立放大的

D:教室里的投影仪所成的像是正立放大的

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A

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How to get siblings (兄弟姐妹) to get along

    One of the greatest gifts of parenthood is seeing your children form a relationship with each other that is independent of you. By giving hem someone else to play with, you can free up some time for yourself. Here are four techniques you can use to help your children appreciate each other while they're young.

    ⒈____ The No.1 thing parents can do to help their kids stay on good terms with each other is not to compare them with each other. Never say “Your sister never. . ”or “Why can't you do what your brother does?”____

    ⒉Try out of the way. Try not to get too involved in your kids' arguments. Learning cooperation and problem-solving is an important skill in life____And don't blame the older one for not “knowing better,” That puts pressure on the older child and leads to unhappiness.

    ⒊Activities and opportunities. Have your kids go to their siblings' games and activities____

    “My kids go to each other's activities, and take part in activities together,” says Patricia Walters-Fischer, mother of two. Not only do her children go, but they also offer support, encouraging each other before a big game or performance and offering comfort when things don't go well.

    ⒋Vacations. Don't ignore the value of a family vacation for bringing siblings together. When kids are away from their friends and forced to spend time together, they often enjoy each other____In fact, a weekend camping trip offers some of the best opportunities for working together, having fun and experiencing something new.

A. Never shout at them.

B. Don't compare.

C. It doesn't need to be anything extremely great.

D. That only serves to fuel the competition.

E. Give them a project, and they will learn how to work together.

F. They may need help solving a conflict, but try not to take sides.

G. Get them involved in one another's lives, so they can have a better appreciation of who their sibling is.