Please go on trying, I’m sure the efforts you are ________ will pay off.
Instead of sending e-mail, Nancy talks with her mother on mobile phone once a week.
— Sorry, Sir. I didn’t quite follow you. — ______. I’ll explain it to you later.
When you’ve finished school, don’t forget to come back to visit your school, ______?
Humans are destroying nature day by day, ________, of course, will cause punishment sooner or later.
The school _______ I visited the other day was not the one _______ I once studied.