普通名词表示泛指的时候不用加the, 如: They are teachers.
以下情况名词前要加the:
1,特指。 Take the medicine.把这药吃了。
2,回指。 He bought a house, I've been to the house.他买了栋房子,我去过那栋房子。
3,指整个群体。 They are the teachers of this school.(指这个学校的全部老师。)
4,指某个群体。 The Chinese people中国人民 ; The Germans德国人。
5,类指。 The dollars ;the fox.