câu 1: Hoàn thành các phương trình phản ứng hóa học sau:
CH3COOH  + ?  ---> CH3COONA + ? + ?
Na  +  ?  --->  C2H5ONa   +    ?
?   +    ?   --->  (CH3COO)3Fe    +   H2O
CH3COOH  +  ? --->  (CH3COO)2Cu +  ?
CH3COOH   +   ?  ----->  CH3COOCH3   +   ?
CH3COOH + ?  --->  (CH3COO)3AL +  H2

B. Write a complaint letter to the head of your school  to tell about using electricity in your class.

 In your class, many students use the electricity for lighting. What makes you worried about that is they use the electricity wastingly.  When they go to class , they turn on the lights everytime, they don’t care about the classrom light or dark. Besides , they switch the fans on although the weather is very cold. They don’t turn off the fans and the lights after using and noone use them. They sometimes forget to turn off all devices in class after schhool, so it waste the electricity too much. You thinhk that the principal ought to ask these students to turn off all the electric devices in all classrooms if not necessary and punish any classes not obey it.

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D. Write a complaint letter to the head of your authorities  to tell about singing karaoke in your neighborhood.

As you know nowsadays , many people sing karaoke  at home too much. It is not necessary to say if they sing their karaoke in normal way  but theydon’t do that. Many of them turn on the volume  too maximize. They make the sound loudly ,and sometime some of their voices are really too bad. This makes their neighbors annoyed. Moreover, some people sing all day with loud sound , even they sing until at middnight . Therefore people who live next door them don’t sleep well and their children can’t  concentrate on learning .The noise makes people not take a rest after a hard working. You think the local authorities  should prohibit and fine heavily these people who sing karaoke by this way.

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D. Write a complaint letter to the head of your authorities  to tell about singing karaoke in your neighborhood.

As you know nowsadays , many people sing karaoke  at home too much. It is not necessary to say if they sing their karaoke in normal way  but theydon’t do that. Many of them turn on the volume  too maximize. They make the sound loudly ,and sometime some of their voices are really too bad. This makes their neighbors annoyed. Moreover, some people sing all day with loud sound , even they sing until at middnight . Therefore people who live next door them don’t sleep well and their children can’t  concentrate on learning .The noise makes people not take a rest after a hard working. You think the local authorities  should prohibit and fine heavily these people who sing karaoke by this way.

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C.  Write a complaint letter to the head of your school to tell about riding bike to school  

As you know nowsadays , many students go to school by bike. It is not necessary to say if they ride their bike in the law but they always break law. Many students ride their  bike too fast and use one hand or no hands by riding. This leads to that the accidents may happen or make the other folk in danger. Some of them may be in danger, too. On the other hand, they often make a line four or five bicycles on the streets and they  always talk or eat when riding, they don’t pay attention on traffic, so it really affects to people who are on the way with them. You think the principal should remind these students in front of all students and punish them heavily.

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B. Write a complaint letter to the head of your school  to tell about using electricity in your class.

 In your class, many students use the electricity for lighting. What makes you worried about that is they use the electricity wastingly.  When they go to class , they turn on the lights everytime, they don’t care about the classrom light or dark. Besides , they switch the fans on although the weather is very cold. They don’t turn off the fans and the lights after using and noone use them. They sometimes forget to turn off all devices in class after schhool, so it waste the electricity too much. You thinhk that the principal ought to ask these students to turn off all the electric devices in all classrooms if not necessary and punish any classes not obey it.

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A. Write a complaint letter to the local authorities to tell about littering garbage around your house in your neighborhood..

These days , many people throw trash around your house in your neighborhood. You are very worried about that beacause they don’t put garbage into the garbage bins. They litter rubbish every where such as on the streets, around houses even onto all channels, streams and rivers. Moreover they also pumped the waste water directly onto the river that makes them seriously polluted and has heavy smell. Many households who live near polluted streams or chanels may catch many illness from them.  On the other hand, littering makes the sightseeings dirty and bad smell. You think the local authorities should prohibit and fine these people who always throw trasheverywhere..............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................