— ________ I borrow these books? — Sorry, only the books over there can be borrowed.
We’ll play basketball ________ Class 3 tomorrow.
Do you know _________ an “o” and _________ “u” in the word “computer”?
The Yangzhi River is one of __________ in the world.
—How can we protect ourselves ________ the earthquake?—We should stay calm first.
Da Shan is _________ at Chinese. He can speak Chinese very _________.