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          公      工

①我和小红去中山____园玩。

②我的爸爸是电____。

③早上，我妈妈坐____共汽车去____司上班。

酒精测试仪可检测驾驶员是否酒后驾车，如图是它的原理图。图中酒精气体传感器的电阻的倒数与酒精气体的浓度成正比，如果测试到的酒精气体浓度越大，那么（）

生命科学活动必须以尊重、保护和挽救         为第一前提。（   ）

    Hello! I' m John. I usually have a busy but happy weekend. I usually do my home- work first. Then I visit my grandparents on Saturday afternoon. They are very happy to see me. On Sundays I often play football with my friends. Sometimes I go swimming or go shopping. But I can't go out this weekend, because the weather report says it's going to rain. I can't play football in the rain. I can only play the piano at home. This is my weekend. What about you?