Would you please tell me your phone number so that we'll ring you up as soon as the remittance arrives?
您能否把电话号码告诉我,以便汇款一到就给您打电话?
Second, if your friends have problems, do not give advice. Ask questions instead, such as What do yo want? How do you feel about it? What are you afraid might happen? They will be able to find answers to any problems themselves, with your support. They