1. Which is specifically concerned with preventing muscle inactivity.
    以防止肌肉活动停止。

2. I don't know what's happening to our little girl. She's changing and I'm concerned about her.
    我不知道我们的小姑娘到底怎么回事。她在变，我很担心她。化妆品，糟糕的音乐，

3. If I care about you, I'm concerned about your growth, and I hope you will become all that you can become.
    关心一个人就是关心他的成长，希望他可以尽其所能有所成就。

4. For our purposes, we are concerned only with one kind of cost----the cost of managing and administering the business.
    就我们的目的而言，我们只关心一种费用 -- 企业行政管理费。