Subclauses are introduced by subordinating conjunctions. If, in other words, you use a subordinating conjunction to link two clauses, the clause following the subordinating conjunction will be the subclause. In the examples below the finite verbs are in red, and the subordinating conjunctions are underlined.

Ik ga vaak naar de universiteit (main clause) omdat ik bijna elke dag college heb (subclause).

I often go to the university because I have lectures nearly every day.

Als ik geen college heb (subclause), ga ik naar de universiteit om te studeren (main clause).

If I don't have any lectures, I go to the University to study.

's Maandags ga ik laat naar de universiteit (main clause) omdat ik dan college heb om zeven uur 's avonds (subclause)

On Mondays I go to university late, because then I have a lecture at seven o'clock in the evening.

The whole sentence (from capital letter at the beginning to full stop at the end) is one main clause. If you start a sentence with a subclause, as in the second example, the subclause takes up the first place in the sentence. That is also why you find the finite verb in the main clause (here: ga) directly after the comma. Ga takes up the second place in the main clause. This complies with the rules for word order in main clauses, where the finite verb is found in second place (see sentence structure).

When a subclause takes up the first place in an entire sentence, a comma has to be placed between the two finite verbs (in the example above between heb and ga).

Note that the subclause in the example above cannot be used as an independent unit.

*Ik bijna elke dag college heb is not a grammatical sentence.