A smile will tell people around you that you are a kind and friendly person. However,many people don’t smile because they think they ugly teeth. For example, one of my classmates, Mile, doesn’t have very nice teeth,so thatis why he seldom opens his mouth.he even says that he has lost cofidence because of his teeth.So it is very important for us to look after our teeth. In fact, a lot of people have this problem.Some people inherit teeth problems from their parents,while others’teeth are damaged because of bad habits,like heavy smoking,eating too much sugar or not brush-ing teeth often.If your teeth are in bad shape, you should see a dentist and ask for help. They can help improve your teeth and tell you how to take care of then.
Smiling can help you to feel more confident and make other people think of you as a more friendly person. If you want to keep healthy,you should not only smile but also laugh. An Indian doctor called Kataria said that young children should laugh about 300 times a day, wile adults should laugh between 7 and 15 times a day. So please take this chance to smile and laugh now!
根据短文内容，选出一个最佳答案填入题前括号内。
【小题1】What has made Mike lose his confidence?
A．His bad habit.B．His bad teeth.C．Not smiling.D．Eating too much sugar.
【小题2】 Many people don’t smile because    .
A．they don’t like smilingB．they think they are ugly
C．their teeth are not beautifulD．they can’t open their mouths
【小题3】 What can a dentist do according to the passage?
A. A dentist can tell you how to improve your bad teeth.
B. A dentist can help you to take care of your bad teeth.
C. A dentist can tell you how to brush your teeth.
D. Both A and B.
【小题4】If you want to keep healthy, you had better    .
A．not smile oftenB．laugh all the time
C．neiter smile nor laughD．smile and even laugh often
【小题5】 How many times should a child laugh every day in doctor Kataria’s opinion?
A．Either 300 or 30 times a day.B．Between 7 and 15 times a day.
C．Around 300 times a day.D．Only 30 times a day.

Good evening, here is the weather report. The weather tomorrow is vrey changeable. It will be sunny in the morning in Beijing. But in the afternoon, the weather will be rainy. In Shanghai, skies will be clear and you can enjoy the bright sunshine in the moning. But it will be clould with no sunshine in the afternoon. In Shenzhen , there will be a light right rain with winds in the morning, and in the after noon it will rain heavily.
1.It will be sunny in the morning in Beijing and      .
2.It will       in Beijing and Shenzhen tomorrow.
3.If you want to go to the park tomorrow in Beijing, you’d better go there in the      .
4.It will be       in the aftenoon in Shanghai.
5.It will be rainy and       in Shenzhen tomorrow.
根据对话内容，补全对话，使其完整﹑通顺。每空一词。
A.we have many rules at school.
B.    ( 1 )do we .For example ,we have to    ( 2 )school uniforms every school day .
A.We usually do,too.We are not allowed to play soccer at school because we don’t have a soccer field
B.Oh,we are lukier than you.We have a big soccer field but we can only    ( 3 )it in P.E.
A.our teachers are very    ( 4 )to us but sometimes they are strict.I think it’s good for us.
B.I    ( 5 )with you.I’ll miss them when I graduate.
如图所示是长度为L＝8.0m水平传送带，其皮带轮的直径为d＝0.40m，传送带上部距地面的高度为h＝0.80m。一个旅行包（视为质点）以v0＝10m/s的初速度从左端滑上传送带。旅行包与皮带间的动摩擦因数μ＝0.60。g取10m/s2。求：
（1）若传送带静止，旅行包滑到B端时，若没有人取包，旅行包将从B端滑落到地面上，则包的落地点距B端的水平距离为多少？
（2）当皮带轮顺时针匀速转动，其角速度为ω0="20" rad/s时，求旅行包在皮带上运动的时间与旅行包落地时的速度；
（3）设皮带轮以不同的角速度顺时针匀速转动，画出旅行包落地点距B端的水平距离s随角速度ω变化的图象（ω的取值范围从0到100 rad/s）。
如图所示是长度为L＝8.0m水平传送带，其皮带轮的直径为d＝0.40m，传送带上部距地面的高度为h＝0.80m。一个旅行包（视为质点）以v0＝10m/s的初速度从左端滑上传送带。旅行包与皮带间的动摩擦因数μ＝0.60。g取10m/s2。求：
（1）若传送带静止，旅行包滑到B端时，若没有人取包，旅行包将从B端滑落到地面上，则包的落地点距B端的水平距离为多少？
（2）当皮带轮顺时针匀速转动，其角速度为ω0="20" rad/s时，求旅行包在皮带上运动的时间与旅行包落地时的速度；
（3）设皮带轮以不同的角速度顺时针匀速转动，画出旅行包落地点距B端的水平距离s随角速度ω变化的图象（ω的取值范围从0到100 rad/s）。
如图所示是长度为L＝8.0m水平传送带，其皮带轮的直径为d＝0.40m，传送带上部距地面的高度为h＝0.80m。一个旅行包（视为质点）以v0＝10m/s的初速度从左端滑上传送带。旅行包与皮带间的动摩擦因数μ＝0.60。g取10m/s2。求：
（1）若传送带静止，旅行包滑到B端时，若没有人取包，旅行包将从B端滑落到地面上，则包的落地点距B端的水平距离为多少？
（2）当皮带轮顺时针匀速转动，其角速度为ω0="20" rad/s时，求旅行包在皮带上运动的时间与旅行包落地时的速度；
（3）设皮带轮以不同的角速度顺时针匀速转动，画出旅行包落地点距B端的水平距离s随角速度ω变化的图象（ω的取值范围从0到100 rad/s）。
如图所示是长度为L＝8.0m水平传送带，其皮带轮的直径为d＝0.40m，传送带上部距地面的高度为h＝0.80m。一个旅行包（视为质点）以v0＝10m/s的初速度从左端滑上传送带。旅行包与皮带间的动摩擦因数μ＝0.60。g取10m/s2。求：
（1）若传送带静止，旅行包滑到B端时，若没有人取包，旅行包将从B端滑落到地面上，则包的落地点距B端的水平距离为多少？
（2）当皮带轮顺时针匀速转动，其角速度为ω0="20" rad/s时，求旅行包在皮带上运动的时间与旅行包落地时的速度；
（3）设皮带轮以不同的角速度顺时针匀速转动，画出旅行包落地点距B端的水平距离s随角速度ω变化的图象（ω的取值范围从0到100 rad/s）。
如图所示是长度为L＝8.0m水平传送带，其皮带轮的直径为d＝0.40m，传送带上部距地面的高度为h＝0.80m。一个旅行包（视为质点）以v0＝10m/s的初速度从左端滑上传送带。旅行包与皮带间的动摩擦因数μ＝0.60。g取10m/s2。求：
（1）若传送带静止，旅行包滑到B端时，若没有人取包，旅行包将从B端滑落到地面上，则包的落地点距B端的水平距离为多少？
（2）当皮带轮顺时针匀速转动，其角速度为ω0="20" rad/s时，求旅行包在皮带上运动的时间与旅行包落地时的速度；
（3）设皮带轮以不同的角速度顺时针匀速转动，画出旅行包落地点距B端的水平距离s随角速度ω变化的图象（ω的取值范围从0到100 rad/s）。
We haven’t decided _______ we’ll go to Shanghai next week.
A．whereB．whenC．whyD．how
We haven’t decided _______ we’ll go to Shanghai next week.
A．whereB．whenC．whyD．how
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