Breakdown of Hij keert de auto om, nadat hij de route heeft bijgesteld.
hij
he / it (referring to a 'de'-word)
de auto
the car
hebben
to have
nadat
after
Questions & Answers about Hij keert de auto om, nadat hij de route heeft bijgesteld.
Why do we use the present perfect (heeft bijgesteld) after nadat, when the first half is in the simple present (keert ... om)?
This is the rule of anteriority (timing) with the word nadat. When you use nadat (after), the action in that clause must logically happen before the action in the main clause. Since the main clause is in the present tense (keert ... om), the nadat clause has to step one tense backwards into the present perfect (heeft bijgesteld) to show it was completed first.
Could I change the word order at the end to ...nadat hij de route bijgesteld heeft?
Yes, absolutely! At the end of a subordinate clause, the auxiliary verb (heeft) and the past participle (bijgesteld) can appear in either order. You will hear Dutch speakers use both interchangeably.
Both omkeren and bijstellen are separable verbs. Why is om separated, but bijgesteld is written as one word?
It is due to the clause types and verb forms. The first part of the sentence is a main clause, where the conjugated verb (keert) goes in the second position and the prefix (om) gets kicked to the end. The second part uses the past participle of bijstellen. Past participles of separable verbs are written as a single word, with ge- sandwiched between the prefix and the verb root (bij-ge-steld).