Välittäjä lähettää sopimuksen sähköpostitse huomenna.

The realtor will send the contract by email tomorrow.

Breakdown of Välittäjä lähettää sopimuksen sähköpostitse huomenna.

• huomenna: tomorrow
• lähettää: to send
• sähköpostitse: by email
• sopimus: the contract
• välittäjä: the realtor

Questions & Answers about Välittäjä lähettää sopimuksen sähköpostitse huomenna.

Why is sopimus in the form sopimuksen?

Because it’s the direct object of the verb lähettää (to send) in a completed/whole sense: send the contract (as a complete item). Finnish typically marks a total object with the genitive -n in singular: sopimus → sopimuksen.
If you meant an incomplete/partial object (e.g., send some of the contract / be sending a contract (not viewed as complete)), you’d more likely see the partitive: sopimusta (context-dependent).

Why is the verb lähettää in the form lähettää (not lähettää or something else), and what person/tense is lähettää?

Lähettää here is the 3rd person singular present form: (he/she/it) sends. The subject is välittäjä (the broker/agent), so the verb agrees in person/number.
Even though the action happens huomenna (tomorrow), Finnish often uses the present tense with a time expression to refer to the future: lähettää … huomenna = will send … tomorrow.

How do I know who välittäjä is exactly—does Finnish have a/the?

Finnish doesn’t have articles like a/an/the. Välittäjä can mean a broker or the broker depending on context. The sentence itself doesn’t force definiteness; you infer it from the situation or prior mention.

What case is välittäjä, and why doesn’t it have an ending?

Välittäjä is in the nominative case, used for the subject of a basic clause. The nominative singular often has no ending (the dictionary form), so it looks “plain.”

What does sähköpostitse mean grammatically, and why not sähköpostilla?

Sähköpostitse is an adverb-like form meaning by email / via email (describing the method/channel). The ending -itse is used in expressions like postitse (by mail) and puhelimitse (by phone).
Sähköpostilla (adessive) can also be used and can sound more concrete/instrument-like (using email / through email). Both can be acceptable, but -itse is very common for “by means of a communication channel.”

Is the word order fixed? Could I move huomenna earlier?

Finnish word order is fairly flexible, but the neutral order is often Subject – Verb – Object – (adverbials), like here.
You can move huomenna for emphasis or style:

• Välittäjä lähettää huomenna sopimuksen sähköpostitse. (neutral, time placed earlier)
• Huomenna välittäjä lähettää sopimuksen sähköpostitse. (emphasizes tomorrow)

Why is huomenna just the basic form—what case is it?

Huomenna is a time adverb meaning tomorrow. It isn’t a noun being declined in a regular case here; it functions as a fixed adverbial form (historically related to essive-like time expressions). You simply use huomenna to locate the action in time.

How is välittäjä formed, and what does it literally mean?

It comes from the verb välittää (to mediate / to convey / to broker). The suffix -jä forms an agent noun: someone who does the action.
So välittäjä is literally a mediator/agent, and in many contexts it corresponds to broker, intermediary, or agent (e.g., real estate broker).

How do I pronounce lähettää and sähköpostitse (any key sound/length issues)?

Two big things: 1) Double letters are long in Finnish. So tt in lähettää is a long t sound.
2) ä is a front vowel (like the vowel in English cat for many speakers, but Finnish is more “pure” and steady).
Rough guides:

• lähettää ≈ LA-he-ttaa (with a long tt)
• sähköpostitse ≈ SÄH-kö-pos-ti-tse (final -tse like tseh, not like English ts in “cats” glued to an e)

Could the object ever be sopimus (nominative) instead of sopimuksen?

Yes, in some specific structures. For example, with an imperative you might see nominative-like object forms in certain patterns, or in passive/other constructions the object marking changes. But in a straightforward active clause like this, lähettää with a total singular object most naturally gives sopimuksen.