J’écris sur mon ardoise avec un feutre noir.

Because je is shortened before a vowel sound. Since écris begins with é-, French uses elision:

• je écris → j’écris

This is very common in French:

• j’aime
• j’habite
• j’écoute

So j’écris simply means I write or I am writing.

It can mean either, depending on context. French often uses the present tense where English might choose either the simple present or the present continuous.

So j’écris sur mon ardoise avec un feutre noir could mean:

• I write on my slate with a black felt-tip pen
• I am writing on my slate with a black felt-tip pen

French usually does not need a separate form like am writing unless the speaker wants to emphasize that the action is in progress.

Sur means on. With écrire sur, French expresses the surface you write on:

• écrire sur une ardoise = to write on a slate
• écrire sur le mur = to write on the wall
• écrire sur une feuille = to write on a sheet of paper

So sur mon ardoise is the natural way to say on my slate.

Ardoise literally means slate. In learning contexts, it can refer to:

• a small slate board
• a classroom writing board
• sometimes a small dry-erase board, depending on context

So the exact translation can vary a little depending on the situation, but slate is the core meaning.

Yes, ardoise is feminine, so normally you would expect ma. But French uses mon, ton, and son before a feminine singular noun that begins with a vowel or mute h.

So:

• ma table
• ma chaise
• but mon ardoise
• mon amie
• son école

This is done mainly for pronunciation, to avoid the awkward sound of ma ardoise.

So mon ardoise still means my slate, even though ardoise is feminine.

French often uses an article where English may omit one. Here, un feutre noir means:

• a black felt-tip pen
• a black marker

Using un is completely normal because French usually wants a determiner before a singular countable noun.

Compare:

• avec un stylo = with a pen
• avec un crayon = with a pencil
• avec un feutre noir = with a black marker

In this sentence, un feutre means a felt-tip pen or marker.

Depending on context, it can refer to:

• a felt-tip pen used for writing or drawing
• a marker

So un feutre noir is a black felt-tip pen / a black marker.

In French, most adjectives come after the noun. So:

• un feutre noir = a black marker
• une voiture rouge = a red car
• un livre intéressant = an interesting book

That is why noir comes after feutre, not before it.

Because noir describes feutre, and feutre is masculine singular.

French adjectives must agree with the noun they describe:

• un feutre noir (masculine singular)
• une ardoise noire (feminine singular)
• des feutres noirs (masculine plural)
• des ardoises noires (feminine plural)

So the adjective matches feutre, not the whole sentence.

Avec means with. Here it introduces the instrument used for writing.

So:

• avec un feutre noir = with a black marker

This is similar to:

• avec un stylo = with a pen
• avec une craie = with chalk

It tells you what tool the person is using.

Yes. The sentence follows a very common pattern:

• J’écris = subject + verb
• sur mon ardoise = where
• avec un feutre noir = with what

So the structure is:

Subject + verb + place/surface + instrument

This is very natural French word order.

A careful approximate pronunciation is:

zhay-kree sur mon-nar-dwaz ah-vek un fuh-tr nwar

A few useful points:

• J’ sounds like the s in measure
• écris ends with a sound like kree
• mon ardoise has linking between the words in natural speech
• r in French is pronounced in the throat, not like an English r

If you want a simpler breakdown:

• J’écris → zhay-kree
• sur mon ardoise → sur mon ar-dwaz
• avec un feutre noir → a-vek un fuh-tr nwar

Yes. This sentence is already natural, but French could also use slightly different wording depending on context. For example:

• J’écris sur mon ardoise au feutre noir.
• J’écris sur mon ardoise avec un marqueur noir.

A small nuance:

• avec un feutre noir focuses on using a black felt-tip pen
• au feutre noir is also natural and can sound a bit more like in black marker / with a black marker

But the original sentence is perfectly correct and natural.