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如图,在试管a中先加入3mL的乙醇,边摇边缓慢加入2mL浓硫酸,再加入2mL无水乙酸,用玻玻棒充分搅拌后将试管固定在铁架台上,在试管b中加入适量饱和碳酸钠溶液.连接好装置,用酒精灯对试管加热,当观察到试管b中有明显现象时停止实验.

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任务型阅读,请阅读下面这篇文章,根据所提供的信息,完成下面的信息卡。

    We often dine out with others, but do you know some basic etiquette (礼节)? If you behave well at the table, it will make your partners happy. But if you don't know how to behave yourself, you will feel embarrassed. Here are some tips for the table etiquette.

    When helping a woman pull her chair to the table, hold it and guide it. Don t shove(碰撞)it against the back of her legs.
     If you're seated at a table with eight or fewer guests, wait for everyone to be served and for the hostess(女主人) to begin eating before you dig in. At a long banquet table, it's OK to start when several people are seated and served.

    If you prefer not to have wine while dining out, don't turn your glass upside down, and don t make a big deal of saying you don't drink. Simply place your fingertips on the rim(边缘) of the glass and say" Not today, thanks."

    When you excuse yourself to go to the restroom, just say" Please excuse me."

    When out with friends or family—even at a fancy restaurant –it's OK to ask for your leftovers(吃剩的饭菜) to be wrapped. But don't do it at a business lunch or dinner.

Information Card

The feeling you may get if you don't behave well at the table

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The number of the guests when waiting for everyone to be served

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The reason why you place your fingertips on the rim of the glass

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The time that don't ask for your leftovers to be wrapped

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The number of suggestions for the table etiquette

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