Mi metas semon en la substraton.

In Esperanto, -as marks the present tense. So metas means put / am putting / place / am placing.

The verb root is met- = put, place.
Some common tense endings are:

• -as = present → metas = put / am putting
• -is = past → metis = put / placed
• -os = future → metos = will put

Also, Esperanto verbs do not change according to the subject:

• mi metas = I put
• li metas = he puts
• ili metas = they put

So there is no special -s just for he/she/it, as in English.

Because semon is the direct object of the verb.

The base noun is semo = seed.
When a noun is the thing directly affected by the action, Esperanto usually adds -n:

• semo = seed
• semon = a seed / the seed as the direct object

In Mi metas semon..., the thing being put is the seed, so it takes -n.

Yes, semon is the direct object. But the -n in substraton is doing a different job.

After a preposition like en, Esperanto can use -n to show direction or movement toward somewhere.

So:

• en la substrato = in the substrate (location)
• en la substraton = into the substrate (movement toward the inside)

In this sentence, the seed is being moved into the substrate, so substraton gets -n.

So the two -n endings here mean different things:

• semon = direct object
• substraton = direction into something

Yes. Very often, en can cover both ideas, and the -n helps show the difference.

• en la substrato = in the substrate
• en la substraton = into the substrate

This is a very common Esperanto pattern:

• sur la tablo = on the table
• sur la tablon = onto the table

So the preposition stays the same, but the -n can show motion toward a place.

Esperanto has a word for the: la.
But it does not have a separate word for a or an.

So:

• semon can mean a seed
• la semon would mean the seed

In this sentence, la substraton suggests a specific substrate that is known from the context, while semon simply means a seed.

So Esperanto often works like this:

• Mi vidas katon. = I see a cat.
• Mi vidas la katon. = I see the cat.

Yes. That would mean I put the seed into the substrate.

The difference is just whether the seed is specific:

• Mi metas semon... = I put a seed...
• Mi metas la semon... = I put the seed...

So both are grammatical; they just express different levels of specificity.

Yes. Esperanto word order is fairly flexible because endings carry a lot of the grammar.

The most neutral order is:

• Mi metas semon en la substraton.

But you could also say things like:

• Semon mi metas en la substraton.
• En la substraton mi metas semon.

These versions may sound more emphatic or stylistically marked, but they are still understandable because:

• semon is marked as the object
• substraton is marked as direction into something

So Esperanto relies less on strict word order than English does.

Yes. Substrato is a valid Esperanto word, especially in scientific, technical, or gardening contexts. It means substrate, growing medium, or the material in which something grows.

In everyday speech, depending on the situation, people might also use words like:

• grundo = soil, ground
• tero = earth, soil

But substrato is useful when you mean something more specific than ordinary soil, such as potting mix or another growing medium.

Esperanto stress is very regular: it always falls on the second-to-last syllable of each word.

So:

• Mi → just mi
• metas → ME-tas
• semon → SE-mon
• en → en
• la → la
• substraton → sub-stra-TA-ton

A rough pronunciation guide for an English speaker:

• Mi ≈ mee
• metas ≈ MEH-tahs
• semon ≈ SEH-mon
• en ≈ en
• la ≈ lah
• substraton ≈ soob-strah-TAH-ton

So the whole sentence is roughly:

mee MEH-tahs SEH-mon en lah soob-strah-TAH-ton

Yes. Meti is a very general verb meaning to put or to place. It focuses on the action of placing something somewhere.

So:

• Mi metas semon en la substraton. = I put/place a seed into the substrate.

It is a straightforward, literal way to describe the action. In a gardening context, other verbs may exist for more specific ideas, but meti is simple and completely clear.