按照句子顺序给图片写序号。
①They'll visit our classroom.
②They'll visit the art room.
③They'll go to the hall.
④They'll go to the library.
⑤They'll meet the teachers in the meeting room.
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我国宁夏回族人多信奉的宗教是( )
需鉴别的物质
方法
A
吸入的气体和呼出的气体
观察颜色
B
氧气和空气
闻气味
C
铁粉和炭粉
用磁铁
D
矿泉水和蒸馏水
过滤后,观察是否有杂质残留在滤纸上