情景交际

根据对话内容,从对话后的选项中选出能填入空白处的最佳选项,并在答题卡上将该项涂黑.选项中有两项为多余选项.

A: Hello,   1  

B. Hello!   2  

A: I'm sorry he is out. He's at the cinema at the moment.

B: Is that Mrs. Brown?

A: Yes.   3   Do you have anything important to tell Tom?  4  

B: Sure. This is Bill. We're going to have a picnic next Sunday. Please remind him to bring

     something to drink.

A: OK. I'll leave the message on his desk.

B:  5   Bye!

A: Bye.  

A. Can I take a message?

B. Thanks a lot.

C. 85776186.

D. This is Tom's mother. E. Speaking.

F. Can I speak to Tom?

G. Who is that speaking?

在等精度观测中，对某一角度重复观测多次，观测值之间互有差异，其观测精度是______的。