Situation 1
You are in a bank and you want to open a new account. The bank representative is describing the different types of accounts and telling you about online banking. You are not sure you understand his explanation of online banking. Ask him for clarification.
Situation 2
You missed an important assignment in one of your university classes. Your professor is telling you about things you can do to improve your grade. But she is not giving a lot of detail and hasn't said how much each thing will raise your grade. Ask for more information.
Situation 3
You are at a doctor's office telling your doctor about a health problem. Your doctor gives you several suggestions to improve the problem. You think you understand but you want to make sure. Check that you've understood what your doctor has said.