铸造合金时，合金熔解时间过长，铸件缺陷是（）。
A.铸件断裂
B.铸件不全
C.铸件夹砂
D.铸件氧化层过厚
E.铸件变大
参考答案：D
阅读短文，判断所给句子是否正确，用“ ”或“ ”表示。
My name is Mike. I'm from London. I'm a student. This is my new storybook. I like storybooks.
My Chinese teacher is Miss Li. Her sweater is red and yellow. My father is an English teacher. My
little sister is Ann. Her hair is yellow. She's a pretty girl. She's two. Her toy train is small but it’s nice.
My grandmother is fat, but I love her.
1. Mike is a Chinese boy.
2. Miss Li is an English teacher.
3. Ann is a student.
4. Mike's grandfather is fat.
5. Ann's hair is black.
6. Miss Li's sweater is blue and yellow.
7. Ann's toy train is nice.
8. Mike's storybook is new.
定义在R上的函数y=f（x）是偶函数，当x≥0时，f（x）=-4x2+8x-3．
（Ⅰ）当x＜0时，求f（x）的解析式；
（Ⅱ）求y=f（x）的最大值，并写出f（x）在R上的单调区间（不必证明）．
”或“ 
”表示。
1. Mike is a Chinese boy. 
2. Miss Li is an English teacher. 
3. Ann is a student. 
4. Mike's grandfather is fat. 
5. Ann's hair is black. 
6. Miss Li's sweater is blue and yellow. 
7. Ann's toy train is nice. 
8. Mike's storybook is new.