有四种物质的溶液：①Ba(OH)₂、②Na₂SO₄、③HNO₃、④FeCl₃，不用其他试剂就可将它们逐一鉴别出来，其鉴别顺序是（  ）

补全对话

从方框中选择最佳选项完成对话, 有两项多余

a. I'm cleaning the house.

b. Is your mother making dumplings with her?

c. What about your father?

d. Yes, we are.

e. She is buying some food in the shop.

f. What's your mother doing?

g. They are making cards for their family and teachers.

Daming: Hi, Tony! Are you getting ready for Spring Festival?

Tony:____ 

Daming: What are the girls doing?

Tony:____

Daming:Sounds great(听起来很好)! Where is your mother?

Tony:____

Daming: What are you doing?

Tony:____

Daming: How hard you are working! And is your sister helping you?

Tony: No, she isn't. She is shopping with my mother.

Daming:____

Tony: Look! He's painting the door there.

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