搜题请搜索小程序“爱下问搜题”
问题 填空题

_________ 是人类在能量转化方面的最早的一次技术革命，导致了以 _________ 作为主要能源的时代的到来，这就是人类第一次能源革命．

答案

钻木取火技术，柴薪．

阅读理解

阅读短文，判断正(√)误(×)。

      Lily is a student of No. 16 Middle School. She's good at English. Her teacher likes her very much. She

often lets her show the visitors around. Lily likes doing that. She often introduces the class building, the library,

the computer room and the music club to them. She likes her school a lot.

( ) 1. Lily is a teacher.

( ) 2. Lily enjoys speaking English.

( ) 3. Lily doesn't like show the visitors around.

( ) 4. She often introduces the dance room.
查看答案
选择题

下列各物质属于钠盐的一 组的是                              [ ]

①KNO3  ②NaCl  ③CuSO4  ④Na2CO3  ⑤NaOH

A．①②③       

B．②④⑤       

C．① ②④      

D．②④

查看答案