题目内容：

补全对话。

根据对话内容，从方框内的选项中选出能填人空白处的最佳选项，其中有两个选项为多余选项。

A：It's very late．Are you still on the computer?

B：Well，yes．1.

A：What kind of e—mails?

B：Some are messages from my teacher and some are from my friends．

A：Do you have to write them back right away?

B：2.．Usually people want a quick reply．

A：3.．

B：I've already had 50 people's address in my address book! And 4.

A： 5.．E—mail is really very convenient(方便的)．

A．I think e—mail is one of the best ways to communicate with others． B．I've got so many e—mails to go through． C．I agree with you． D．Of course! E．How many e—mails addresses have you had? F．I feel like playing computer games． G．I am not sure whether I'm right or wrong．