The U.S. first lady Michelle Obama, arrived in China on March 20, 2014 for _______ six-day visit, focusing on _______ importance of cultural exchanges.
May I have a rest? I have already finished ________the report.
We can't work out the physics problem. Can you tell us ________?
Try to sing more English songs,and you will find it interesting ________a foreign language.
We can make a fire ________the room warm so that we can chat for a while.
The girl ________ by the lake yesterday.