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Lesson 33: Dass or was? Ob — the "whether/if" particle

Vocabulary: Technology

Completing this lesson will add to your overall progress:

VocabularyA2+1%B1+3%B2+0.5%
GrammarA2+2%B1+4%

How to work with this lesson

  1. Read the rule — understand the logic (5 minutes)
  2. Translate the exercises in writing — check against the key
  3. Say it out loud — slowly, consciously, watching word order in the subordinate clause
  4. Speed up — drill the matrix until it flies out on autopilot

You can already build sentences with um...zu and damit. Now add three new connectors: dass, ob, was. They glue two clauses into one — and all three send the verb to the end. One principle, three tools.

Part 1: Three words — three situations

In English: "I know that he's coming", "I don't know whether/if he's coming", "I don't know what he's doing". Three meanings — three different German words:

  • dass = "that" (a fact, a statement)
  • ob = "whether / if" (yes/no — you don't know which)
  • was = "what" (you don't know the content)

The iron rule: the verb goes to the end.

Part 2: The main hack — "Do you know, or don't you?"

Know a fact → dass. Don't know yes/no → ob. Don't know what/who/where → was/wer/wo.

  • Ich weiß, dass er kommt. — I know that he's coming. (Fact.)
  • Ich weiß nicht, ob er kommt. — I don't know whether he's coming. (Yes/no?)
  • Ich weiß nicht, was er macht. — I don't know what he's doing. (Content?)

English-speaker note: English "if" is ambiguous. "I don't know if he's coming" — does that mean "whether"? Yes. In German, ob is ONLY the yes/no "if". The conditional "if" (= "if it rains, we'll stay home") is wenn, not ob. Don't mix them.

Part 3: Word order — verb at the end

In a subordinate clause with dass / ob / was, the conjugated verb sits at the last position.

Main clauseConnectorSubject...Verb (last!)
Ich weiß,dassermorgenkommt
Ich frage,obdudie Apphast
Ich verstehe nicht,wassiedortmacht

Three things:

  1. Verb is always last in the subordinate clause. Not second — last.
  2. Comma is mandatory before dass / ob / was.
  3. Perfekt in a subordinate clause — hat/ist drops to the very end: Ich weiß, dass er die App heruntergeladen hat.

Trap! Don't confuse dass and das. Dass = the conjunction "that" (with two s). Das = the article or demonstrative pronoun (with one s). Ich weiß, dass er kommt. Das ist gut. Germans drilled this in school the same way English speakers drill "its/it's".

Verb-final rule = the biggest mental shift for English speakers. English keeps the verb in second position no matter what: "I know that he is coming tomorrow." German says: "Ich weiß, dass er morgen kommt." The verb literally migrates to the end. Practice this until it's reflex.

Part 4: Dass, ob, was — in detail

Dass — "that" (a fact, a statement)

Use after verbs of knowing, thinking, feeling: wissen, glauben, finden, sagen, hoffen.

ExampleTranslation
Ich weiß, dass das WLAN hier schlecht istI know that the Wi-Fi here is bad
Wir hoffen, dass das Update bald kommtWe hope that the update comes soon
Er glaubt, dass das Smartphone zu teuer istHe thinks that the smartphone is too expensive

Ob — "whether / if" (uncertainty, yes/no)

Use when the answer is "yes" or "no", but you don't know which:

ExampleTranslation
Ich weiß nicht, ob das WLAN funktioniertI don't know whether the Wi-Fi works
Er fragt, ob ich die App heruntergeladen habeHe's asking whether I downloaded the app
Prüf mal, ob das Smartphone geladen istCheck whether the smartphone is charged

Was / wer / wo — "what / who / where" (asking about content)

Use when you don't know the specific information:

ExampleTranslation
Ich weiß nicht, was diese App machtI don't know what this app does
Zeig mir, wie man das hochlädtShow me how to upload that
Sag mir, wer das gepostet hatTell me who posted that

Next up: Lesson 34 — Weil, denn. Time prepositions: vor, in, seit. You'll learn to give reasons two ways — "because" twice — and find out why their word order is different. Plus the trick of seit + Präsens for "I've been doing X for Y years".

Lesson 33: Dass or was? Ob — the "whether/if" particle · Deutsch · Glottos Matrix