—Do you know anything about the players of our school basketball team?—Yes. They are _______ young boys between the age of thirteen and fifteen.

We're tired because we have ________ yin.

—Have you ___________ been to Beijing? —Yes. But only once.

The car is quite small, _______ if you have children.       

---Anna can’t go to school these days . ---____________? ---Because she is in____________ hospital now.