“细小的”用英语怎么说？

他感到细小的沙砾不断打在膝盖上。He felt tiny bits of grit and sand peppering his knees.捕食性动物的眼睛能感觉到最细小的动静.The eyes of predators are highly sensitive to the slightest movement.强有力的手指箍着她那细小的手腕.Strong fingers encircled her tiny wrists....