题干

在“探究摩擦力大小与哪些因素有关”的实验中,同学们提出了以下几种猜想:

A.与物体质量大小有关;B.与物体间的接触面积大小有关

C.与物体运动速度有关;D.与物体间接触面的粗糙程度有关

实验中有一较长的水平粗糙桌面、一个带构的长方体木块和一支弹簧测力计可供使用.

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     Teaching your child to read can be one of the most rewarding(值得的) experiences you have as a parent.

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      Nothing can replace the head start(起步时的优势)that a child receives from becoming familiar with books and the way that the written word sounds when read aloud. If your child sees that reading is important to you, then he will be much more likely to want to learn how to read himself.

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       If your child shows interest in learning letters and looking through books, he may be ready to begin learning to read. Learning how to read cannot be rushed. If your child has no interest in learning his letters, then wait a month or so and try again.

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      You can make this fun, such as saying “I see a k-æ-t-cat” whenever you see a cat. The sound of a letter is much more important than a letter's name because the child will need to combine the letter sounds to make words.

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      Some children learn their letters faster by seeing or hearing them, while other children learn letters by using their bodies. Encourage your child to draw the letter and then paste pictures of something that begins with that sound onto the letter. Sing songs about the letter. Read your child a story that repeatedly uses that letter sound.

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      Rather than try to teach a child 26 new letters at one time, focus on one letter a day or a week. This enable the child to master each letter sound and feel proud of himself/herself for doing so.


A. Read to your child daily.

B. Show your child your love for reading.

C.  Make sure your child is ready to begin learning how to read.

D. Focus on one letter at a time.

E. Teach your child the sound of each letter.

F. Use sight, sound and touch as you teach each letter.