填入适当的词补全对话，每空一词。

A: What's your ____, Madam?

B: I feel very weak. I can hardly do any work, Doctor.

A:____ long have you been like this?

B: Ever since last month.

A: Do you____a headache?

B: No, I ____.

A: Do you sleep well at night?

B: Yes. I sleep very well.

A: Do you often have breakfast?

B: No. I have never had breakfast, and I have____ food for lunch because I would like to be thin.

A: Oh, I see. There's not much wrong  ____ you. You have to take more food and have three meals a day. And do some sports every day. Then you will get____ soon.

抛物线y=（x﹣3）（x+1）与x轴交于A，B两点（点A在点B左侧），与y轴交于点C，点D为顶点．

长郡本部生物竞赛组的同学们在岳麓山进行野外观察时，其中一位同学在溪流中发现了一种背腹扁平，有口无肛门的动物，你认为可能下列动物中的哪一种（　　）

据史料记载，16、17世纪时，西属拉美国家墨西哥和秘鲁的白银生产量约占世界的85%，其中近半数流入了中国，这主要是因为（       ）