Al - Although

The subordinating conjunction al expresses a concessive relation: there appears to be some contrast between the two elements connected by al.

Al can be replaced by alhoewel, hoewel or ofschoon, but triggers a different word from (al)hoewel and ofschoon. The concessive clause introduced by al has the word order of a main clause: the finite verb (hebben in the examples below) is in second position.

Wij zijn geslaagd voor het examen, hoewel we weinig gestudeerd hebben.

We have passed the exam, although we have not studied much.

Wij zijn geslaagd voor het examen, al hebben we weinig gestudeerd.

If the concessive clause introduced by al follows the main clause, al also triggers a different word order. There is no inversion in the main clause (unlike a main clause following a concessive clause introduced by (al)hoewel and ofschoon) :

Hoewel het al 12 uur is, ben ik nog niet moe.

Although it is already12 o'clock, I am not tired yet.

Al is het al 12 uur, ik ben nog niet moe.