Learn Hardcore German: Wenn dir übel ist, trink langsam Tee und bleib im Bett. - If you feel sick, drink tea slowly and stay in bed.

Wenn du übel bist would sound wrong or at best mean something very different, like “if you are evil/bad” (because übel can also mean “bad, nasty” about a person’s character or actions).

What case is dir, and why is it used here?

dir is dative singular of du.

Certain sensations and states in German are expressed with the dative person:

Mir ist kalt. – I’m cold.
Ihm ist langweilig. – He is bored.
Uns ist heiß. – We are hot.
Dir ist übel. – You feel sick.

In all these, the person is in the dative, and the adjective describes an impersonal state affecting that person.

So in Wenn dir übel ist, dir is dative because ist übel is being “experienced” by you, not treated as a normal subject–predicate like du bist krank.

Why does the verb ist go to the end in Wenn dir übel ist?

Wenn introduces a subordinate clause (a dependent clause). In German subordinate clauses, the conjugated verb goes to the final position.

Main clause: Dir ist übel. (Verb in second position)
Subordinate clause: Wenn dir übel ist, … (Verb last)

General pattern:

Wenn
- [subject / objects / other stuff] + verb (conjugated) at the end

What kind of clause does wenn introduce here? Could you use als or falls instead?

Here, wenn introduces a conditional clause: if you feel sick.

Wenn dir übel ist, … = If you feel sick, …

Alternatives:

falls – also “if”, often a bit more hypothetical or formal:
- Falls dir übel ist, trink … = In case you feel sick, drink …
als – not correct here. Als is used mainly for:
- when in the past, single event:
  - Als ich klein war, … – When I was small, …
- Not for this conditional “if” meaning.

So here, wenn (and optionally falls) is fine; als is wrong.

Why is there a comma after ist?

In German, you must put a comma between a subordinate clause and the main clause.

Subordinate clause: Wenn dir übel ist
Main clause: trink langsam Tee und bleib im Bett

So the comma marks the boundary:

Wenn dir übel ist, trink langsam Tee und bleib im Bett.

Why are the verbs trink and bleib used without du?

They are imperative forms (commands) for du.

In German:

du trinkst → imperative: trink!
du bleibst → imperative: bleib!

With du, the pronoun is usually dropped in the imperative:

Trink langsam Tee. – (You) drink tea slowly.
Bleib im Bett. – (You) stay in bed.

You can say Trink du langsam Tee, but that sounds more emphatic or contrastive (e.g. You drink tea slowly (not him)).

What exact verb forms are trink and bleib? How are they formed?

They are imperative singular (du) forms:

Infinitive: trinken
- du-form: du trinkst
- imperative singular: trink! (drop -en, drop -st ending)
Infinitive: bleiben
- du-form: du bleibst
- imperative singular: bleib!

You will also see the variant with -e:

trinke!, bleibe!

Both trink!/trinke! and bleib!/bleibe! are grammatically correct; the short forms without -e are more common in everyday speech.

Is word order important in trink langsam Tee? Could I say trink Tee langsam?

Both are possible:

Trink langsam Tee.
Trink Tee langsam.

In short sentences like this, the difference is minimal. Some nuances:

Trink langsam Tee. – The adverb langsam comes right after the verb, sounding like drink slowly (and what you’re drinking is tea).
Trink Tee langsam. – Puts a tiny bit more focus on Tee first, then adds how to drink it.

Both are fine and natural. German word order with adverbs can be flexible, especially in such short sentences.

Why is there no article before Tee? Why not einen Tee?

Without an article, Tee is treated as a mass noun, like “tea in general” or “some tea”.

Trink Tee. – Drink (some) tea.
Trink einen Tee. – Drink a (cup of) tea.

Here, the advice is general: drink tea slowly, not necessarily one specific portion. So using Tee without an article is natural.

Why is it im Bett and not ins Bett?

The preposition in takes:

dative for location (where?) → im Bett (in dem Bett)
accusative for movement to a place (where to?) → ins Bett (in das Bett)

In this sentence:

bleib im Bett – stay in bed (location, no movement)

Compare:

Geh ins Bett. – Go to bed. (movement → accusative)
Du liegst im Bett. – You are lying in bed. (location → dative)

Is bleib missing an -e? Should it be bleibe?

Both are correct imperative forms:

Bleib im Bett. – very common in spoken and written German.
Bleibe im Bett. – more formal, or slightly old-fashioned in tone, but still correct.

Modern everyday German usually drops the final -e in du-imperatives (komm!, geh!, mach!, bleib!).

Can I use schlecht instead of übel? What’s the difference?

Both are possible, but they carry slightly different feels:

Mir ist übel. – I feel nauseous / queasy (strong association with nausea).
Mir ist schlecht. – Often also “I feel sick”, but can be more general: I feel bad / unwell, or my stomach is off.

In the context of advice about staying in bed, übel strongly suggests nausea (e.g. stomach bug, food poisoning).
schlecht can mean that too, but is a bit broader and less specifically “queasy”.

Why is Tee capitalized, but dir is not?

In German:

All nouns are capitalized: Tee, Bett, Haus, Auto, etc.
Pronouns like dir, du, mir, ich are not capitalized (except at the beginning of a sentence or in some very formal letters, where Sie/Ihnen etc. are capitalized as formal “you”).

So Tee and Bett are capitalized because they are nouns; dir remains lowercase as a pronoun.