根据短文内容填空，每空不超过4个单词。
Mary didn’t understand such sentences as “You are yellow.” “She has a green thumb( 拇指 ).” “ He has told me a white lie.” And so on. So she went to her English teacher for help.
Mary : Mrs. Smith, there is a color in each of these sentences. Could you tell me what they mean?
Mrs. Smith: In English, yellow sometimes means afraid. Blue means sad. A person with a green thumb grows plants well. And a white lie is not a bad one.
Mary: Would you give me an example for a white lie?
Mrs. Smith: Certainly. Now I give you some cakes. In fact you don’t like them, but you won’t say so. Instead you say, “No, I’m not hungry.” That is a white lie.
Mary : Oh, I see. Thank you very much.
小题1:Mary did not understand the sentences and asked Mrs. Smith for ______________.
小题2:You are blue today means you feel _____________.
小题3:I don’t have a _______________, so all my plants are dead.
小题4:My friend didn’t want me to know the fact of the accident. He told me_____________.
小题5:This passage is about _____________ and their meanings.
2Z(g)，已知X2、Y2、Z的起始浓度分别为0．1mol/L、