人工拌水泥混凝土混合物的顺序为（）。A．砂子、水泥干拌后，再掺石子干拌，最后加水拌和

根据对话内容及方框中所给的选项补全对话。选项中有一项是多余的。（5分）
( Li Lei is a Chinese exchange student in America. He is chatting with Jason in his host family. )
Jason : Hi, Li Lei! Here is your juice.
Li Lei: Thanks, Jason.
Jason : Not at all.   小题1: 
Li Lei; That's right. How time flies!
Jason :  小题2:
Li Lei; Yes, 1 do. The teachers are very helpful, and the students are active and confident.
Jason : It's kind of you to say so. And I hear you Chinese students are very hard-working.
Li Lei: We sure are.   小题3:
Jason : By the way, do you have any plans for this weekend?
Li Lei:   小题4: How about you?
Jason : I want to do some volunteer work. Shall we go to the old people's home visit?
Li Lei; Sounds great!  小题5: 
Jason : I believe you will like it.

A. Nothing much. B. How long have you been here? C. It'll be a new experience to me.        D. You have been here for months, right? E. We are strict in our schoolwork.        F. Do you get used to the school life here?