例句與造句

1. since most fertile lands have been cultivated, the expansion of the agricultural land has been extended to marginal and problem soils with poor nutrient supply
   因為大多數肥力較高的土壤都在進行種植，所以增加農業耕地面積只有向邊際地區和土壤養分含量低并存在某些問題的土壤上擴展。
2. It's difficult to find problem soil in a sentence. 用problem soil造句挺難的