Jobben er vanskelig; til gjengjeld er lønnen god.

Because they are in the definite singular form.

• en jobb = a job
• jobben = the job

and

• en lønn = a salary / pay
• lønnen = the salary / the pay

In this sentence, Norwegian is talking about a specific job and its pay, so the definite forms are used.

The noun is lønn. It already ends in -nn, and the definite ending is -en. So:

• lønn
  • -en → lønnen

This is completely normal in Norwegian spelling. It is similar to how English sometimes keeps all the letters when adding an ending.

Til gjengjeld means something like:

• in return
• in compensation
• on the other hand
• but as a trade-off

In this sentence, it means that although the job is difficult, there is a compensating positive fact: the pay is good.

So the logic is:

The job is difficult; in return / on the other hand, the pay is good.

Because Norwegian normally follows the V2 rule in main clauses: the finite verb must be in the second position.

The first element in the second clause is til gjengjeld, so the verb er must come next:

• Til gjengjeld er lønnen god.

Not:

• Til gjengjeld lønnen er god.

This is very common in Norwegian. Compare:

• I dag er han hjemme.
• Derfor kommer vi sent.

When something other than the subject comes first, the verb usually comes before the subject.

Because lønn is a common-gender singular noun, and the adjective here is predicative (it comes after er).

Adjective agreement after er works like this:

• common gender singular: god
• neuter singular: godt
• plural / definite contexts: gode

Since lønnen is singular and common gender, we get:

• Lønnen er god.

Compare:

• Huset er godt.
• Forholdene er gode.

Yes, you could say Lønnen er bra, and it would sound natural.

But god lønn / lønnen er god is especially idiomatic when talking about salary or pay. In many contexts, Norwegian prefers god with things like:

• god lønn
• god kvalitet
• god service

So god is a very natural choice here, even though bra is also possible.

The semicolon links two closely connected main clauses:

• Jobben er vanskelig
• til gjengjeld er lønnen god

It shows a strong connection between the two ideas: one negative point and one compensating positive point.

A comma is often avoided here because both parts are full clauses. A period would also be possible:

• Jobben er vanskelig. Til gjengjeld er lønnen god.

The semicolon just makes the contrast feel neatly balanced.

Usually, lønn is a general word for pay, wages, or salary.

Depending on context, English might translate it differently:

• god lønn = good pay
• månedslønn = monthly salary
• timelønn = hourly wage

So in this sentence, lønnen could be understood as the pay or the salary.

Here, jobben most naturally means the job—the specific position or role.

Norwegian jobb can sometimes refer more loosely to work, but in this sentence it sounds like a particular job:

• Jobben er vanskelig = The job is difficult

If you wanted something more like the work is difficult, you might also see words like arbeidet depending on context.

A rough pronunciation guide is:

YOB-ben er VAN-ske-lig; til YENG-jeld er LØN-nen goo

A few useful notes:

• j in jobben sounds like English y
• gj in gjengjeld is often pronounced like a y-sound
• ø has no exact English equivalent; it is similar to the vowel in French peu or German schön
• god here is pronounced more like goo than like the English word god

The rhythm is usually with a slight pause at the semicolon: Jobben er vanskelig; til gjengjeld er lønnen god.

Yes. You could rearrange it, but the emphasis would change.

For example:

• Lønnen er god, men jobben er vanskelig.
• Til gjengjeld er lønnen god, selv om jobben er vanskelig.

The original sentence starts with the negative point first and then gives the compensation. That makes til gjengjeld especially effective, because it signals: here is the upside.