--What’s this?--It’s__ backpack.--Where’s__ backpack?--It’s on the bed.
Their school has more than two _____ teachers and _____ students.
_______ of the materials I listened to at the beginning of the exam _______ easy.
_______, Coca-Cola began to enter China’s market.
______black—headed gulls(红嘴鸥) come to Kunming to spend their winter every year.
Helen is my friend. She is in ______ at Beijing No.11Middle School.