题目

某城市利用人工建立的湿地对生活污水进行净化处理,还在湿地养殖鱼、虾、鸭,获得良好的经济效益,如图. (1) 在如图人工湿地所列举的生物中,属于脊椎动物的是. (2) 细菌、真菌等微生物的呼吸作用是净化污水的重要途径,为了提高分解的效率,可采取的有效措施是. (3) 一定量的生活污水排入人工湿地中,引起藻类大量繁殖,进而食藻浮游动物大量繁殖,藻类开始减少,接着又引起浮游动物减少,上述例子可以说明根据各题后括号内的要求完成下列句子。【1】Was his uncle having dinner when you arrived at his home?(补全肯定答语)Yes,he_______.【2】The Smiths were playing cards when I saw them.(改为否定句) _____________________________________________.【3】Mike was readinginthelibrary when I called him.(对画线部分提问) What____________________________?【4】Susan wrote a letter to her cousin last night.(用at 7∶00 last night替换last night改写句子)_______________________________________________ 【5】Jill took photos.Lisa listened to the radio.(用while连成一句)________________________________________________
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