用括号中所给词的适当形式填空。

1. You're so ______ (luck). This is the last ticket for Guiyang

2. ______ you ______ (finish) reading the novels yet?

3. I don't know what             (do) tomorrow.

4. Would you like             (help) me with my maths?

5. Will you please             (help) me fill in the blanks?

6. We can't live _______ (with) water.

7. What are the _______ (different) between Haiku and a five-line poem?

8. Sam needs _______ (wear) a white shirt.

数字签名技术的主要功能是：( )、发送者的身份认证、防止交易中的抵赖行为的发生。

A．保证信息传输过程中的完整性

B．保证信息传输过程中的安全性

C．接收者的身份验证

D．以上都是