Die plank hangt een beetje scheef.

Here die means that: that plank / that board.

Dutch uses die and dat as demonstratives:

• die = that for de-words
• dat = that for het-words

Because plank is a de-word (de plank), you say die plank.

So:

• de plank = the board / the shelf
• die plank = that board / that shelf

Because plank takes the article de, not het.

In Dutch, demonstratives have to match the noun’s grammatical gender/class:

• de noun → die
• het noun → dat

Since it is:

• de plank

it becomes:

• die plank

Plank usually means a board, shelf, or plank.

Which English word fits best depends on context:

• a loose wooden board
• a shelf attached to a wall
• a plank in a more general sense

So in this sentence, die plank could mean:

• that board
• that shelf

Dutch often uses hangen (to hang) where English might use be plus an adjective.

So instead of saying something like That shelf is a bit crooked, Dutch naturally says:

• Die plank hangt een beetje scheef.

Literally, that is:

• That board/shelf hangs a little crooked.

This is very normal Dutch. It emphasizes the way the object is hanging.

Hangt is the third person singular present tense of hangen (to hang).

Conjugation:

• ik hang
• jij hangt
• hij/zij/het hangt

The subject here is die plank, which is singular, so:

• Die plank hangt

Een beetje means a little, a bit, or slightly.

It softens the statement:

• scheef = crooked / slanted
• een beetje scheef = a bit crooked / slightly crooked

This is very common Dutch:

• een beetje moe = a bit tired
• een beetje duur = a bit expensive
• een beetje scheef = a bit crooked

Scheef means something like:

• crooked
• slanted
• tilted
• not straight

In this sentence, it suggests the plank or shelf is not level or straight when hanging.

Depending on context, English translations could be:

• That shelf is hanging a bit crooked.
• That board is a little crooked.
• That shelf is slightly slanted.

That is normal Dutch word order.

The basic structure is:

• subject + verb + other information + adjective/complement

Here:

• Die plank = subject
• hangt = verb
• een beetje = modifier
• scheef = complement describing how it hangs

So:

• Die plank hangt een beetje scheef.

Putting scheef at the end sounds natural because it completes the idea of how the plank is hanging.

Because scheef is not being used directly before a noun here.

Compare:

• de scheve plank = the crooked plank
  Here the adjective comes before the noun, so it usually gets an ending: scheve.
• de plank hangt scheef = the plank hangs crooked
  Here the adjective comes after the verb, so it stays plain: scheef.

So in this sentence, scheef is correct.

Not as a normal main clause.

The standard main-clause order is:

• Die plank hangt een beetje scheef.

Dutch requires the finite verb in second position in a main clause, so hangt must come early.

Die plank scheef hangt would only make sense as part of a longer subordinate structure, for example:

• Ik zie dat die plank scheef hangt. = I see that that shelf is hanging crooked.

Sometimes small shifts are possible, but Die plank hangt een beetje scheef is the most natural order.

For example:

• Die plank hangt een beetje scheef. → most natural
• Die plank hangt scheef. → without a bit
• Die plank hangt nogal scheef. → rather crooked
• Die plank hangt heel scheef. → very crooked

So een beetje normally comes before the adjective it modifies.

Yes, very natural.

A Dutch speaker would easily say this about:

• a shelf on a wall
• a sign
• a picture frame
• anything hanging unevenly

Very similar sentences are:

• Dat schilderij hangt scheef. = That painting is hanging crooked.
• Je lamp hangt een beetje scheef. = Your lamp is hanging a bit crooked.

So this is a useful everyday pattern:

• [thing] hangt (een beetje) scheef