Learn Hardcore Dutch: Tom is gestrest, omdat het tentamen langer duurt dan hij had verwacht. - Tom is stressed because the exam lasts longer than he expected.

omdat is a subordinating conjunction. It starts a subordinate clause and sends the finite verb to the end:
- Tom is gestrest, omdat het tentamen langer duurt.
  (…because the exam lasts longer.)
want is a coordinating conjunction. It just links two main clauses; the word order after want stays like a main clause (verb in second position):
- Tom is gestrest, want het tentamen duurt langer.

Nuance:

omdat puts more focus on the reason itself and sounds a bit more “structured”.
want feels a bit more conversational and adds an extra piece of information.

In your sentence you could use want instead, but then the clause after it would be:

Tom is gestrest, want het tentamen duurt langer dan hij had verwacht.

Why is the word order omdat het tentamen langer duurt and not omdat het tentamen duurt langer?

In Dutch, subordinate clauses (introduced by words like omdat, dat, als, wanneer, terwijl etc.) send the finite verb to the end of the clause.

Main clause: Het tentamen duurt langer.
→ verb (duurt) in second position
Subordinate clause: omdat het tentamen langer duurt
→ subject (het tentamen) + adverb (langer) + verb at the end (duurt)

So:

Correct (subordinate clause): omdat het tentamen langer duurt
Incorrect in standard Dutch: omdat het tentamen duurt langer

In main clauses you would say:

Het tentamen duurt langer (verb second, adverb after it).

Why do we say het tentamen instead of de tentamen?

Dutch nouns are either de-words (common gender) or het-words (neuter). The noun tentamen happens to be a het-word, so you must say:

het tentamen
de tentamens (plural always uses de)

There’s no simple rule that tells you whether a noun is de or het; it’s mostly lexical knowledge you have to learn with each word:

het examen (the exam)
het tentamen (a type of exam, usually at university)
de toets (test)

So you memorize het tentamen as a fixed pair.

What exactly is a tentamen? Is it the same as an examen?

They’re related but not identical in everyday Dutch:

tentamen
- Typically used for (partial) exams at university or college.
- Often one of several graded tests that together form a course.
examen
- General word for “exam”, especially final exams (school-leaving exams, driving test, etc.).
- At universities, some people also say examen, but tentamen is very common for course exams.

In many contexts you can translate tentamen simply as exam in English, but in Dutch it carries that specific higher-education flavor.

Why is it langer and not something like meer lang?

Dutch usually forms comparatives (more X) by adding -er to the adjective:

lang → langer (long → longer)
groot → groter (big → bigger)
mooi → mooier (pretty → prettier)

You don’t say meer lang in standard Dutch, just like you don’t say “more long” in normal English. So:

Het tentamen duurt langer. = The exam lasts longer.

You do use meer with many other word types (adverbs, nouns, some adjectives that don’t take -er), but lang → langer is the regular, correct comparative.

Why do we say langer dan hij had verwacht and not langer als hij had verwacht?

Dutch makes a clear distinction in comparisons:

For inequality (more/less than), use dan:
- langer dan hij had verwacht (longer than he had expected)
- groter dan ik dacht (bigger than I thought)
For equality (as … as), use als:
- zo lang als hij had verwacht (as long as he had expected)
- even groot als ik (as big as I am)

So here we’re comparing unequal lengths (it’s longer), so standard Dutch requires dan, not als: langer dan hij had verwacht.

In many dialects you’ll hear groter als, langer als, but this is considered incorrect in standard written Dutch.

Why is it hij had verwacht and not hij heeft verwacht or hij verwachtte?

All three are grammatically possible, but they don’t mean exactly the same:

hij had verwacht (past perfect)
- Lit. “he had expected”.
- Places the expectation before another point in the past or present situation.
- Here, the reference point is the current exam duration.
- The idea: the exam is now running / we are now seeing its actual length; before that, he had a (wrong) expectation.
- Very natural with dan in comparisons:
  - Het duurde langer dan hij had verwacht.
hij verwachtte (simple past)
- “he expected”.
- Focuses more on his past mental state, less on the timing relation.
- Tom is gestrest, omdat het tentamen langer duurt dan hij verwachtte.
  → Also possible, just slightly different stylistic choice.
hij heeft verwacht (present perfect)
- “he has expected”.
- Sounds odd here; the present perfect in Dutch usually connects a past event with the present result, but in this comparative construction … dan hij heeft verwacht is not idiomatic.

So had verwacht is the most natural: it clearly marks that his expectation was already in place before we are comparing it with the actual duration.

Why is the order dan hij had verwacht and not dan hij verwacht had?

In subordinate clauses with more than one verb (a verb cluster), Dutch allows some variation in order:

dan hij had verwacht (auxiliary before participle)
dan hij verwacht had (participle before auxiliary)

Both are grammatically correct in standard Dutch.

Differences:

hij had verwacht is more common and neutral in everyday speech and writing.
hij verwacht had can sound slightly more formal, old-fashioned, or regional, depending on context.

So the chosen version dan hij had verwacht is simply the most typical, natural-sounding one.

Is gestrest an adjective or a past participle, and why is it spelled that way?

gestrest is originally the past participle of the verb stressen (“to be under stress / to stress out”), but in practice it’s used mainly as an adjective, just like English stressed:

Tom is gestrest. (predicate adjective)
een gestreste student (an stressed student – attributive adjective)

About the spelling:

The official standard spelling is gestrest (one s in the ending, one t).
You will see people write gestresst, but that is not the official spelling.

So in correct standard Dutch you should write: Tom is gestrest.

Could we also say Tom heeft stress, omdat …? How is that different from Tom is gestrest?

Yes, both are possible, with a small nuance:

Tom is gestrest.
- Focus on his current state or mood: “Tom is stressed out / tense / on edge right now.”
Tom heeft stress.
- Literally “Tom has stress”.
- Suggests he is suffering from stress as a condition or symptom; it can sound a bit more like talking about a (possibly longer-term) problem.

In everyday speech, both can be used for a short-term situation; is gestrest sounds a bit more colloquial and direct (like English “is stressed”).

Is the comma before omdat necessary: Tom is gestrest, omdat …?

The comma here is optional but common.

You may write:
- Tom is gestrest omdat het tentamen langer duurt dan hij had verwacht.
- Tom is gestrest, omdat het tentamen langer duurt dan hij had verwacht.

Style:

Many style guides recommend a comma when the main clause is followed by a longer subordinate clause, especially to improve readability.
Unlike want, where a comma is obligatory (…, want …), omdat does not absolutely require it.

So both versions are correct; the comma mainly helps the reader see the sentence structure more clearly.

Can hij refer to someone other than Tom here? How do we know who hij is?

Grammatically, hij can refer to any masculine singular person previously mentioned in the context. In this isolated sentence, the most natural reading is:

hij = Tom, because:
- Tom is the only previously mentioned person.
- Dutch, like English, usually links a pronoun to the most recent suitable antecedent unless there’s a clear reason not to.

However, if the broader context introduced another male person right before this sentence, hij could theoretically refer to that person instead. If you want to make it 100% unambiguous that it’s Tom, you can repeat the name:

… dan Tom had verwacht.

Could we say het tentamen zal langer duren dan hij had verwacht instead of duurt?

Yes, that’s possible, but it changes the time reference slightly.

het tentamen duurt langer
- Present tense.
- Often used for:
  - something happening right now (the exam is currently taking longer than he expected), or
  - a scheduled future event (Dutch often uses present for timetabled future events).
het tentamen zal langer duren
- Future tense with zal (“will”).
- Emphasizes that we’re talking about a future event and a prediction.

So:

If the exam is already going on or is a fixed schedule you’re describing, duurt is very natural.
If you’re clearly predicting about a future exam, zal langer duren fits better.