1. allergic to 对|……过敏

Oh man! Something in this room is making my eyes itch, I must be allergic to something.

2. at sb’s service 愿为某人服务

I am at your service at any time.

3. around the clock 24小时不停

Martha studied around the clock for management exam.

4. as far as I know 就我所知

5.at home with 对…..很熟悉

She is at home with problems like this.