推进会议进程应遵循的原则不包括______。A．学会倾听 B．善于引导 C．控制节奏

In the following essay, each blank has four choices. Choose the most suitable one from the four choices and write down in the answer sheet. There are two types of key technology: private key and public key. Private - key encryption methods are called (66) ciphers, information is encrypted with (67) both the sender and receiver hold privately. Public - key encryption methods are called (68) ciphers, (69) created for each user, encryption key and decryption key ale (70) .

A．a key

B．two keys

C．three keys

D．four keys

1929年，中山大学（）教授出版了我国第一部比较教育专著《各国教育比较论》。

— What's the matter with you?

— After the long walk,my legs ____ and I couldn't go any further.[      ]

A. gave out

B. gave off

C. gave in

D. gave up

在胎头下降曲线中"-1"表示

A．胎头颅骨最低点在坐骨棘平面下lcm
B．胎头颅骨最低点在坐骨棘平面上1cm
C．胎头颅骨最低点在坐骨结节平面下1cm
D．胎头颅骨最低点在坐骨结节平面上lcm
E．以上都不对