— What do you think of this one?— It looks nice. But I ________ why you choose (选择) this one for me.
— Have you ever been to Canada?— Yes, I there last year with my parents.
— How long may I your bike?— For a week. But you mustn’t it to others.
— ?— The one behind the tree.
— Must we clean the classroom now?— No, you needn't. It after school.
— It’s so cold today.— Yes, it’s colder than it was yesterday.