He is so busy. He cannot afford enough time with his son _______ he wants to.
The book was written in 1946, ___ ___ the education system has witnessed great charges.
—Where did you get to know her? —It was on the farm ___ ___ we worked.
Some pre-school children go to a day-care center, ___ ___ they learn simple games and songs.
After graduation she reached a point in her career ___ ___ she had to decide what to do.
He was educated at the local high school, ___ ___ he went on to Beijing University.