particles fraction的用法和樣例：
例句
- The aggregates, composed of the primary particles, retain sufficient water and nutrients.
由原顆粒組成的團聚體要能保持充分的水分和養分。 - The base surge of dirt particles moves outward from the center of the explosion and is subsequently carried downwind.
由塵埃顆粒組成的基浪從爆炸中心向外移動(dòng)，繼而順風(fēng)散開(kāi)。
