原式=1-x-yx+2y×(x+2y)2(x+y)(x-y)
=1-x+2yx+y
=-yx+y．
故答案为-yx+y．
阅读理解。
Alice is an American girl. She is thirteen. She is now in Beijing with her parents. She doesn't know
much Chinese. She can't speak Chinese well. Sometimes her friends do not understand her.
It's Sunday morning. She's going to the zoo to see the pandas. She is waiting at the bus station. At the
bus station she asks a boy how to go to the zoo. But the boy can't understand her. Then she takes out
(拿出) a pen and some paper. She draws a panda on it and shows the picture to the boy. The boy
smiles and shows the way to the zoo right now.
1. Alice is in Beijing with her________.
A. brother
B. sister
C. uncle
D. father and mother
2. Alice can speak ________Chinese.
A much
B. little
C. few
D. many
3. Alice goes to the zoo________.
A. on her bike
B. on a bus
C. in a car
D. on a train
4. Alice is going to the zoo to see________.
A. her friends
B. the tigers
C. the monkeys
D. the pandas
5 .The boy________.
A. shows her the way
B. doesn't know the way
C .goes to the zoo with her
D. gives a map to her
虚寒型肺痿的特征性症状是（）
A.吐浊唾，质粘稠
B.吐涎沫，质清稀
C.吐白痰，质稀薄
D.吐清水，质淡薄
E.以上都不是
