【单选题】实验室用高锰酸钾制纯净氧气时,下列做法错误的是
A.
在试管口放一团棉花,防止高锰酸钾粉末进入导管
C.
导管口开始有气泡放出时就立即收集,防止生成的气体跑掉
D.
用高锰酸钾制取所需氧气停止加热时,先要把导管移出水面,然后再熄灭酒精灯
【单选题】I often go swimming with my father______Sunday.
【简答题】句型转换。 l. My father often watches TV in the evening.(改为否定句) My father _____ _____ often TV in the evening. 2. The girls are waiting for a famous actor.(改为一般疑问句) _____ the girls waiting _____ a famous a...
【单选题】I often see my mother __________ chess with my father after supper.
【单选题】—Which of the caps will you take? —I’ll take _______,one for my father ,the other for my brother.
【单选题】企业所拥有的资产从财产权利归属来看,一部分属于投资者,一部分属于
【单选题】My father often ________ Beijing for Shanghai.
【判断题】发动机VTEC的切换不受车速限制。 ( )
【单选题】My father often ( )football match on TV.
【单选题】My father often ____books late in the evening.