居民所用石油液化气的主要成分是丁烷,在使用过程中,常有一些杂质以液态沉积于钢瓶中,这些杂质是[ ]
A.甲烷和丙烷
B.乙烷和甲醛
C.乙烷和丁烷
D.戊烷和己烷
答案:D
认真读短文,选择正确的答案。
I am a boy. My name is Li Ming. I am ten. I am a pupil. I have two friends. One is Danny. The other one
is Jenny. Jenny is a pupil, too. We are in the same row. We like Danny.
1. How old is Li Ming?[ ]
A. He's ten.
B. He's eleven.
2. Is Li Ming a teacher?[ ]
A. Yes, he is.
B. No, he isn't.
3. Is Jenny a pupil?[ ]
A. Yes, she is.
B. No, she isn't.
4. How old is Danny? [ ]
A. Sorry, I don't know.
B. She's eleven.
5. Are Li Ming and Jenny in the same class? [ ]
A. Yes, they are.
B. No, they aren't.
可引起中性粒细胞核右移的疾病是()
A.巨幼细胞性贫血
B.白血病
C.急性大出血
D.败血症
E.溶血性贫血