实验室用KMnO4制O2,应选用的发生装置是( )
A:
B:
C:
D:
— I must say it is the most delicious duck I have ever eaten. — __________. I'm glad you enjoyed it.
选择每组单词中不同类的一个。
①____A.shoes B.skirt C.hat D.size
②____A.colour B.pink C.white D.brown
③____A.ask B.cry C.magic D.visit
④____A.wear B.give C.clever D.nod
⑤____A.pair B.great C.beautiful D.tiny
日月星辰的东升西落,原因是