Unlike in French, there are times when a noun is not preceded by an article at all.
Generalizing
One occasion where no article can be found before a noun or noun phrase is when the speaker or writer is generalizing or being non-specific about something. For example:
Pens are becoming obsolete. (Pens, in general, are no longer needed).
Children should be seen and not heard. (In general, we shouldn't be bothered by children).
In the news this week, trees mysteriously disappeared. (We won't be specific and tell you which trees disappeared).
Conventions
Articles are generally not used when referring to names of sports, academic subjects, people, titles, languages, nationalities (unless referring to a nation’s population), and countries. For example:
The soccer is a fun game.
The Biology is an easy course.
The Doctor Penfield has a street named after him.
The Chinese is a difficult language to learn.
The Canada won a medal.