写出下列反应文字表达式及反应类型 (1)铁在氧气中燃烧：____________

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问题填空题

写出下列反应文字表达式及反应类型

(1)铁在氧气中燃烧：____________ 基本反应类型：__________

(2)航天工业中常用液氢和液氧做火箭的推进剂：___________ 基本反应类型：__________

答案

（1）铁＋氧气四氧化三铁；化合反应

（2）氢气 + 氧气水；化合反应

阅读理解

We go shopping almost every day. We have many choices of' the places to buy things. A supermarket

is the right place for you. There are some good points buying things at the supermarket.

First: You buy things at the supermarket at a low price. You pay much more in the big store to buy the

same goods.

Second: You decide what to buy all by yourself' at the supermarket. And you don't have troubles from

the shop assistant at the big store.

Third: There are more choices of' goods to buy at the supermarket. You can buy many things for a

week's use at a time: it saves us much money and time.

In a word, it is better to buy things at a supermarket.

根据短文内容,判断正(T)误(F).

( )1. The things at the supermarket are cheap.

( )2. You buy things from the shop assistant at the supermarket.

( )3. There're all kinds of goods at the supermarket.

( )4. It takes you much time to buy many things at the supermarket.

单项选择题 A型题

HIV感染人体后主要导致的系统损害是（）。

A.消化系统

B.循环系统

C.免疫系统

D.呼吸系统

E.骨骼系统