Ystäväni on vilpitön.

My friend is sincere.

Breakdown of Ystäväni on vilpitön.

• olla: to be
• minun: my
• ystävä: the friend
• vilpitön: sincere

Questions & Answers about Ystäväni on vilpitön.

What does the ending -ni in ystäväni mean?

The ending -ni is a possessive suffix meaning “my”.
So:

• ystävä = friend
• ystäväni = my friend

Finnish can mark possession directly on the noun with these suffixes:

• -ni = my
• -si = your (singular)
• -mme = our
• -nne = your (plural)
• -nsä / -nsa = his/her/their

In this sentence, ystäväni alone already contains the idea “my friend” without any separate word for my.

Why is there no separate word like minun (“my”) in the sentence?

You can say:

• Minun ystäväni on vilpitön.

but it’s not necessary. The possessive suffix -ni already expresses “my”.

The patterns are:

• Ystäväni on vilpitön. = My friend is sincere.
• Minun ystäväni on vilpitön. = My friend is sincere. (slightly more emphatic or contrastive)

In everyday spoken language, people often say instead:

• Mun ystävä on vilpitön. (colloquial: mun instead of minun, and no suffix)

All three are understandable, but your sentence is perfectly correct and quite neutral/standard.

Can ystäväni mean both “my friend” and “my friends”?

Yes, ystäväni is formally ambiguous between singular and plural:

• ystäväni = my friend (singular)
• ystäväni = my friends (plural)

The number is usually clear from the verb and the adjective:

• Ystäväni on vilpitön.

  • on = is (3rd person singular)
  • vilpitön = sincere (singular form)
    → “My friend is sincere.” (singular)

• Ystäväni ovat vilpittömiä.

  • ovat = are (3rd person plural)
  • vilpittömiä = sincere (plural partitive)
    → “My friends are sincere.” (plural)

So in your sentence, the singular verb and adjective tell us it means “my friend”.

What grammatical role and case does ystäväni have in this sentence?

In Ystäväni on vilpitön, ystäväni is:

• the subject of the sentence
• in the nominative case (the basic dictionary form)

There is no article in Finnish, so one nominative form ystäväni covers what English would express as “my friend”, “a friend of mine”, or sometimes “the friend of mine”, depending on context.

What is on, and why is this form used?

On is the 3rd person singular present tense of the verb olla = “to be”:

• minä olen – I am
• sinä olet – you are (singular)
• hän / se on – he / she / it is
• me olemme – we are
• te olette – you are (plural)
• he / ne ovat – they are

Because the subject ystäväni is singular (“my friend”), you use the singular form on:
Ystäväni on vilpitön. = My friend is sincere.

Why isn’t there any word for “he” or “she” in the sentence?

Finnish usually doesn’t need a personal pronoun if the subject is already expressed:

• Ystäväni on vilpitön.
  Literally: My-friend is sincere.

You would not normally say “Ystäväni hän on vilpitön” (like “My friend he is sincere”) unless you want a very strong emphasis or a specific contrast in spoken language.

So the subject ystäväni is enough by itself; adding hän (he/she) would usually sound redundant.

What form is vilpitön, and why not something like vilpitöntä?

Vilpitön is an adjective meaning “sincere, genuine, candid” in its basic (nominative singular) form.

In copula sentences of the type:

• [Nominative subject] + on + [adjective]

the adjective is usually in nominative singular if the subject is a single, countable thing:

• Ystäväni on vilpitön. – My friend is sincere.
• Opettaja on väsynyt. – The teacher is tired.

Forms like vilpitöntä (partitive singular) appear in other structures or for different nuances, but here the simple property “is sincere” is expressed with the nominative vilpitön.

How would I say “My friends are sincere”?

You change the verb and the adjective, but ystäväni can stay the same:

• Ystäväni ovat vilpittömiä.

Breakdown:

• Ystäväni = my friends (here understood as plural)
• ovat = are (3rd person plural of olla)
• vilpittömiä = sincere (plural partitive form of vilpitön)

So:

• Ystäväni on vilpitön. – My friend is sincere.
• Ystäväni ovat vilpittömiä. – My friends are sincere.

Can I change the word order, like “Vilpitön on ystäväni”?

Yes, Finnish word order is fairly flexible, and you can move things for emphasis:

• Ystäväni on vilpitön.
  Neutral: My friend is sincere.

• Vilpitön on ystäväni.
  Emphasises vilpitön; more like “Sincere is what my friend is” or “It is sincere that my friend is.” This sounds marked/poetic or like strong contrast.

The most natural everyday order for this sentence is the original:

• Ystäväni on vilpitön.

What is the difference between vilpitön and rehellinen, both often translated as “honest”?

Both can relate to honesty, but they have different nuances:

• vilpitön

  • sincere, open-hearted, genuine, without ulterior motives
  • focuses on inner sincerity and openness

• rehellinen

  • honest, not lying, not cheating
  • focuses on truthfulness and moral honesty

So:

• vilpitön ystävä – a sincere friend, emotionally genuine and straightforward
• rehellinen ystävä – an honest friend, someone who tells the truth and doesn’t deceive you

In Ystäväni on vilpitön, the emphasis is on your friend being sincere and genuine, not just “not a liar.”

How do you pronounce Ystäväni on vilpitön?

Approximate pronunciation (using English-like hints):

• Ystäväni ≈ “ystah-vah-nee”

  • y: like French u in tu (front, rounded vowel)
  • ä: like a in cat, but a bit clearer and more open
  • stress on the first syllable: YS-tä-vä-ni

• on ≈ “on”, like British on (short o)

• vilpitön ≈ “vil-pi-tøn”

  • ö: like French eu in peur, or German ö in schön
  • stress on the first syllable: VIL-pi-tön

Overall rhythm: YS-tä-vä-ni on VIL-pi-tön – each word stressed on its first syllable, all vowels clearly pronounced.