The prepositions om, door, na, alvorens, in plaats van, and zonder can mark the beginning of a short subclause. If they do, the subclause always contains a "te + infinitive" construction. You can read more about this under short subclauses.
Om
'Om' means 'in order to' or 'for'. It receives special attention here because there are a few verbs where we can omit 'om'. Instead of "Ik probeer om te slapen" (I try to sleep), we can also say "Ik probeer te slapen" (again: I try to sleep). 'Proberen' now looks like an 'infinitive + te' verb but it really is a an om-construction in disguise.
The disguised om-verbs are listed below. They all have something to do with a wish, desire, or command. Note that you can only omit 'om' when it is preceded by one of the verbs in the list below.
aanmoedigen
to encourage
| Ze werden aangemoedigd om gezonder te gaan leven.
| They were encouraged to live a healthier life.
|
bedoelen
to intend
| Ik bedoelde om iets heel anders te zeggen.
| I meant to say something completely different.
|
beloven
to promise
| Hij belooft om vanaf nu op tijd te komen.
| He promises to be on time from now on.
|
bevelen
to command
| Ze beval hun om naar haar kantoor te komen.
| She ordered them to come to her office.
|
opdragen
to command
| Ze dragen je op om langer te blijven.
| They tell (order) you to stay longer.
|
proberen
to try
| Ik probeer om zonder wekker wakker te worden.
| I try to wake up without an alarm-clock.
|
streven
to strive, aim
| We streven ernaar om alle zwerfkatten een huis te geven.
| We try (have the ambition) to give all straycats a home.
|
verlangen
to desire
| Ze verlangden ernaar om terug naar huis te gaan.
| They longed (for it) to go home.
|
verzoeken
to request
| Mag ik jullie verzoeken om jullie voeten van tafel te halen?
| May I ask you to take your feet of the table?
|
vragen om
to ask for
| Ze vroegen je om mee te komen.
| They asked you to come along.
|
wensen
to wish, prefer
| De premier wenst om niet te komen.
| The prime minister prefers not to come.
|
Notes:
- Beloven and wensen are also 'dat verbs'.
* Vragen is mentioned with the preposition om because there are several other combinations possible: vragen naar and vragen aan do not mean the same as vragen om. See also the phrasal verbs list.
Om-verbs in the perfect tense
Because the verbs that follows after -often invisible- om are situated in a short subclause, the past participle in the main clause does not turn into an infinitive. Because dat-verbs are subject to the same principle, I refer to dat-verbs in the perfect tense for more information.
Ze had hun bevolen om naar haar kantoor te komen.
| She had ordered them to come to her office.
|
Ik heb geprobeerd om zonder wekker wakker te worden.
| I have tried to wake up without an alarm-clock.
|
We hebben ernaar* gestreefd om alle zwerfkatten een huis te geven.
| We have tried (aimed) to give all straycats a home.
|
Ze hebben jullie gevraagd om mee te komen.
| They have asked you to come along.
|
Note:
- Ernaar is a pronominal adverb: naar het turns into ernaar. So why do we use er here? A preposition (in thise case, naar) needs to be followed by an object. Because streven naar requires an object within the same clause, we use a provisional er. The 'real' object is the entire subclause "(om) alle zwerfkatten een thuis te geven."
Questions? 
