A:空气中的二氧化碳和土壤中的有机物
B:土壤中的无机盐
C:空气中二氧化碳和土壤中的水分
D:空气中的氧气和土壤中的有机物
六位数由三位数重复构成,如256256,或678678等等,这类数不能被何数整除( )
(____) No, I don't like winter.
(____) Which season do you like best, Lily?
(____) Winter. I can play with snow.
(____) So I like autumn best. It's always sunny and cool.
(____) What about you? Do you like winter, too?
(____) It's too cold.
完成下列活动不需要使用调查方法( )