化简：2x²-3x²=____

①是通过完善制度倒逼企业提升质量安全保障能力

②是我国规范乳粉产品市场秩序的根本之举

③是国家运用行政手段加强对市场的监管

④有利于引导市场主体规范交易方式和行为

— Hello! Kangkang! ____.

— Hi, Xiao Lei! I’m going to the post office.

— ____.

— I’m going to send some clothes and books to the students in Wenchuan.

— You’re really warm-hearted. ____.

— No, they can’t. Their school buildings fell down and the government (政府is rebuilding schools for them.

— It’s good news. I hope they can go to school early.

— ____. Oh, what about you? What will you do for the students there to show your love?

— ____.

— Money? That’s good. Shall we go to the post office together?

— Good idea. Let’s go!

买玩具。