The two friends _____ on the Internet for three hours, and they would go on till the next morning.

Do you know everyone from Class One– Er…, I know some of ______.

______my mailing address is different from my living address? —-Then you must write both in the form

___ ___ travel all over China during the summer holiday

Nanjing isn’t so large __________ Shanghai,however, it’s the second __________ city in East China.