After a 3-week winter vacation， students usually some weight when they return to school.

It is difficult for a teacher togive attention tochildren in a large classWe should reform the situation in order to meet each child’s needs

________ in the queue for half an hour, Tom suddenly realized that he had left his wallet at home.

need you buy _______ forme tomorrow

Selina has recently ___________ Chinese painting to please her grandmother who was born in China．