5. Could you tell her John called?
能否转告她约翰找她？
还能这样说：
Tell her there was a call from John.
Please tell her John called when she comes back.
6. Please ask her to call me back as soon as she comes back.
请让她一回来就给我回电话。
还能这样说：
Please have her return my call when she returns home.
Would you tell her to give me a ring when she's back?
谚语：
Least said, soonest mended.
言多必失。
7. Please tell him to come to school quickly.
请告诉他快点来学校。
还能这样说：
Please tell him to come to school at once.
Please let him know and come to school soon.
应用解析：
tell against (sb.) 成为对（某人）不利的证据；
tell apart 分清，区分；
tell on 告发；说……坏话；影响到……
8. No, thank you. It's not urgent.
谢谢，不用了，没有什么要紧事。
还能这样说：
No, thank you. It's not important.
No, thank you. There isn't anything pressing.
应用解析：
be urgent for sb. (to do) 急切地催促某人（做）；
be urgent with sb. for (to do) 坚持要求某人（做）