— What is he busy doing?
— Doing the experiment _____ (complete) the science project.
The skirt is very beautiful，Lucy （真正地）likes it．
They （花费）an hour volunteering in the old people's home every afternoon．
Thanksgiving Day is c on the fourth Thursday in November in America．
Foreigners are surprised to see many great d of China．
Lao She Teahouse d the changes in Chinese society over fifty years．