Vahvuus näkyy vaikeassa tehtävässä.

Because vaikeassa tehtävässä is in the inessive case, which often means in, inside, or more generally in the context of something.

• vaikea = difficult
• tehtävä = task
• vaikeassa tehtävässä = in a difficult task

Both the adjective and the noun take the same case ending:

• vaikea → vaikeassa
• tehtävä → tehtävässä

This matching is very important in Finnish: adjectives usually agree with the noun in case and number.

The verb näkyä does not usually take a direct object the way many English verbs do. It means things like to be visible, to show, or to be seen/apparent.

So the sentence is structured more like:

• Strength is visible in a difficult task
• Strength shows in a difficult task

The phrase vaikeassa tehtävässä tells the situation or context where the strength becomes visible.

Näkyy is the 3rd person singular form of näkyä.

Depending on context, näkyä can mean:

• to be visible
• to show
• to be seen
• to become apparent

In this sentence, it is probably best understood as:

• shows
• is visible
• becomes apparent

So Vahvuus näkyy vaikeassa tehtävässä means that strength becomes visible when there is a difficult task.

Because näkyä and nähdä are different verbs.

• nähdä = to see
  
  • hän näkee = he/she sees
• näkyä = to be seen / to be visible / to show
  • se näkyy = it is visible / it shows

So:

• Hän näkee vahvuuden. = He/she sees the strength.
• Vahvuus näkyy. = Strength is visible / shows.

In your sentence, the subject is vahvuus, so näkyy is the correct verb.

Yes. Vahvuus is the subject.

You can see this because:

• it is in the basic dictionary form, not in an object case
• the verb näkyy agrees with a singular subject
• semantically, strength is the thing that shows/is visible

So the structure is:

• Vahvuus = subject
• näkyy = verb
• vaikeassa tehtävässä = adverbial phrase showing context

Finnish does not have articles like English a/an and the.

So vahvuus can mean:

• strength
• the strength
• sometimes even a strength, depending on context

And vaikeassa tehtävässä can mean:

• in a difficult task
• in the difficult task

The exact meaning depends on context, not on an article.

Yes. Finnish word order is fairly flexible, although neutral word order is often subject–verb–other elements.

The original sentence:

• Vahvuus näkyy vaikeassa tehtävässä.

This is a natural, neutral way to say it.

You could also say:

• Vaikeassa tehtävässä vahvuus näkyy.

This puts more focus on in a difficult task.

Changing the word order usually changes emphasis rather than the basic meaning.

Because the adjective must match the noun’s case.

The noun is tehtävässä:

• tehtävä
  • -ssä = tehtävässä

So the adjective also takes the inessive ending:

• vaikea
  • -ssa = vaikeassa

This is normal Finnish agreement:

• iso talo = big house
• isossa talossa = in a big house

So:

• vaikea tehtävä = a difficult task
• vaikeassa tehtävässä = in a difficult task

The basic form is tehtävä.

Here is the breakdown:

• tehtävä = task
• tehtävässä = in the task

The ending -ssä is the inessive case ending. Because of vowel harmony, some words take -ssa and some take -ssä.

Since tehtävä contains front vowels like ä, it takes -ssä.

This is because of vowel harmony, an important Finnish pattern.

• Words with back vowels (a, o, u) usually take back-vowel endings like -ssa
• Words with front vowels (ä, ö, y) usually take front-vowel endings like -ssä

Examples:

• talossa = in the house
• koulussa = in the school
• metsässä = in the forest
• tehtävässä = in the task

So tehtävässä uses -ssä because the word has ä.

Literally, the inessive case often corresponds to in, but in actual usage it is often broader than physical location.

Here it means something like:

• in a difficult task
• when dealing with a difficult task
• in the context of a difficult task

So it is not necessarily about being physically inside anything. It is about the situation where strength becomes visible.

Yes, depending on context. Vahvuus can mean:

• strength in a general abstract sense
• a strength in the sense of a strong point or advantage

For example:

• Kärsivällisyys on hänen vahvuutensa. = Patience is his/her strength.

In your sentence, vahvuus is probably understood as strength in a general sense, but context could make it feel more personal too.

By itself, it sounds like a general statement or observation.

Finnish often uses the singular without articles to express general truths:

• Vahvuus näkyy vaikeassa tehtävässä.

This sounds like:

• strength shows when the task is difficult
• real strength becomes apparent in a hard task

If you wanted to make it clearly about a specific task, the surrounding context would usually make that clear.