It turned out that one of the children I thought a girl was _______ a boy.
China’s economic development has made rapid progress in the past years and young people have made great contribution to this progress.
The little boy is dirty from head to foot because he ______ in the mud all morning.
I’m writing this letter ________ my mother, who wants to thank you for your nice gift.
Some graduates _______ pictures with them _______ getting a job in the company.
When it comes to consumer society, protest groups are insisting that some of our money ______ to the third world.