选词填空。

1. Etta ______________ (have, has) a teddy bear.

2. Let's go to the ______________ (clothes, toy) department to buy a new skirt.

3. She ______________ (don't, doesn't) like the clothes there.

4. She ______________ (finds, looks for) him everywhere.

5. It's time ______________ (go, to go) to sleep.

下图甲为人体内细胞与外界物质交换示意图，乙是内环境示意图，请回答：

当④中水分减少时，其浓度改变会刺激（）产生（），促进肾小管对水分的重新吸收，使尿量减少。