You don't and you shouldn't. There are many problems with translation of the definite article in this site. As a general rule: In the SUBJECT of a sentence the definite article is used in Spanish to generalize the subject. If you want to say "bread is good" you'd say "el pan es bueno", this means bread in general is good. With the countable nouns, the SUBJECT of a sentence is generally pluralized in addition to being modified by a definite article : Las gallnas no vuelan (means: Hens (as a general category of birds) don't fly).