The kids love to buy a doughnut as a snack on their way home from school.

doughnut 是名词，由 dough（生面团）和 nut（坚果）组成，字面意思是"面团坚果"，实际指一种环形油炸甜点，中文称为"甜甜圈"。这种甜点通常中间有洞，表面可能撒糖粉或淋糖浆。