In order to talk to several people at the same time on the Internet,______.
A. you have to speak fast and fluently
B. you should speak with wit and humor
C. one should pay much attention to the use of exact words
D. you have to express your ideas in a brief way
I don't really work here; I ______until the new secretary arrives.
A. just help out
B. have just helped out
C. am just helping out
D. will just help out
To save time on the Internet,______.
A. some people leave their letters in the dustbin
B. some people never use "shift" in their writing
C. people seldom use capital letters and punctuation
D. many people leave the capital or punctuation
下列头孢菌素类对绿脓杆菌有效的是( )
A. 头孢噻啶
B. 头孢氨噻
C. 头孢氨苄
D. 头孢呋新
E. 头孢孟多
微信支付 
支付宝支付