Earthquakes always happen , so it is difficult to know when they come.

The islands developed on their own for 80 million years and _______ have many rare animals found nowhere else[ ]

What do you think of the lecture of Li Yang’s Crazy English — I think it’s _______ , but someone thinks it’s much too ________.

Zeng Xiaoxian in Love Apartment（爱情公寓）_____very young and cool.

I have three basketballs. I want to buy a ______one.