—Excuse me, where did you get the book?—I borrowed it from the  ________. 

. ---- You like to surf the Internet. Do you know the meaning of “WWW”?---- Of course. It means _______.

The ____ of some wild animals reminds us __ the problems on environment.

wish you a pleasant journey, my son! Thanks, mom. I’ll give you a __as soon s I arrive in Beijing

I received a number of ________, but ________ of them is valuable to me.