授课：XX211授课：XX112授课：XX授课：XX1+1=2加号等于号授课：XX授课：XX减号等于号授课：XX213授课：XX213授课：XX213授课：XX213授课：XX授课：XX1+2=3授课：XX授课：XX+=授课：XX授课：XX授课：XX授课：XX授课：XX+=1 + 1 = 2-=2 - 1 = 1授课：XX1 + 2 = 3+=3 - 1 =2-授课：XX2 + 1 = 3+=-=3 - 2 = 1授课：XX1 + 1 =2 + 1 =23授课：XX3 - 1 = 3 - 2 = 21授课：XX3 - 1 =2 + 1 =23授课：XX31123填授课：XX212111111122313221211333231121223321122112133211233112授课：XX3 - = 2 - 1 = 22 + = 32 + 1 = + 1 = 33 - 2 = 3 - = 1 - 2 = 1 + 1 = 21 + = 22 - = 12 - 1 = - 1 = 11 + 2 = 1 + = 3 + 2 = 33 - 1 = 1 + 1 = 211112321213312123授课：XX 盘子里一共有盘子里一共有3个苹果，小明拿走了个苹果，小明拿走了1个苹个苹果，还剩下几个苹果？果，还剩下几个苹果？授课：XX再见 授课：XXThank you!31