Das Kind badet in der Badewanne.

Because Kind is a neuter noun in German, so its nominative singular article is das.

• der = masculine
• die = feminine
• das = neuter

So the correct form is das Kind.

A useful thing to remember: grammatical gender in German does not always match real-world sex. A child may be a boy or a girl, but the noun Kind is still grammatically neuter.

Because the subject is das Kind, which is third person singular: it bathes / the child bathes.

The present-tense forms of baden are:

• ich bade
• du badest
• er/sie/es badet
• wir baden
• ihr badet
• sie/Sie baden

So with das Kind, you need badet.

In this sentence, it means something like is taking a bath or is bathing.

German often uses the simple present tense where English would prefer is + -ing. So:

• Das Kind badet.
  = The child is bathing / is taking a bath.

A very literal English translation The child bathes is grammatically possible, but in normal English it sounds more like a habit than an action happening right now.

Because in is a two-way preposition in German.

With two-way prepositions:

• dative = location, no movement
• accusative = direction, movement toward somewhere

Here the child is already in the bathtub, so this is location, not movement. That is why German uses the dative:

• in der Badewanne = in the bathtub

If you wanted to say the child gets into the bathtub, you would use the accusative:

• Das Kind geht in die Badewanne.
  = The child goes into the bathtub.

Because Badewanne is a feminine noun, and feminine nouns change article in the dative singular.

For a feminine noun:

• nominative: die Badewanne
• accusative: die Badewanne
• dative: der Badewanne

So after in in a location meaning, you get:

• in der Badewanne

This is a very common pattern in German.

Yes. German very often forms compound nouns by writing them as one word.

Badewanne is made up of:

• Bade- = bath-
• Wanne = tub

So Badewanne literally means bath tub.

Also, all nouns in German are capitalized, which is why both Kind and Badewanne start with capital letters.

Because baden is normally used without a reflexive pronoun when it means to bathe / to be bathing.

So Das Kind badet is natural and correct.

English learners sometimes expect something like The child bathes itself, but German does not usually need that here.

Compare:

• Das Kind badet. = The child is taking a bath.
• Das Kind wäscht sich. = The child washes itself / is washing.

So waschen is commonly reflexive in this kind of meaning, but baden usually is not.

Yes, but it means something slightly different.

• Das Kind badet in der Badewanne.
  This focuses on the action: the child is bathing.

• Das Kind ist in der Badewanne.
  This focuses on the location: the child is in the bathtub.

The second sentence does not necessarily mean the child is bathing. The child could just be sitting there, playing, or about to bathe.

Yes, sometimes.

In German, baden can be used for bathing in water more generally, especially in contexts like lakes, rivers, or the sea. Depending on context, it can overlap with swim or go bathing.

For example:

• Wir baden im See.
  = We swim / go bathing in the lake.

But in Das Kind badet in der Badewanne, the context makes it clear that it means taking a bath, not swimming.

The sentence follows the normal German main-clause word order:

Das Kind | badet | in der Badewanne

That is:

• subject
• finite verb
• other information

In German main clauses, the finite verb typically comes in second position. This sentence is a straightforward example of that rule.