Fosforlu kalemle başlığı çizdim, tükenmez kalemle de altına kısa bir not yazdım.

-le means with or by means of.

So:

• fosforlu kalemle = with a highlighter
• tükenmez kalemle = with a ballpoint pen

This suffix is the shorter form of ile. So kalemle and kalem ile mean the same thing, but the attached form is very common in everyday Turkish.

Because this de is the separate word meaning also / too.

So tükenmez kalemle de means also with a ballpoint pen or and with a ballpoint pen too.

This is different from the suffix -de/-da meaning in / on / at, which is written attached to the word.

Compare:

• evde = at home
• ben de = me too

Because başlığı is a definite direct object.

In Turkish, a specific or known direct object usually takes the accusative ending. Here, the speaker is referring to the title/headline, not just any title.

• başlık = title / heading
• başlığı = the title as a direct object

So:

• başlık çizdim would sound more like I marked/drew a title or some title
• başlığı çizdim = I marked the title

Because of consonant softening.

Some Turkish words ending in p, ç, t, k soften when a vowel-initial ending is added. Here:

• başlık
  • -ı → başlığı

So the final k changes to ğ.

This is a very common pattern:

• kitap → kitabı
• ağaç → ağacı
• kanat → kanadı
• başlık → başlığı

Because kısa bir not is an indefinite object: a short note, not the short note.

In Turkish, indefinite singular direct objects often appear without the accusative ending:

• kısa bir not yazdım = I wrote a short note

If the note were specific and already known, you would use the accusative:

• kısa notu yazdım = I wrote the short note

So this sentence contrasts nicely:

• başlığı = specific
• kısa bir not = non-specific

Altına means under it / underneath it / below it.

It comes from alt = lower part / underside / below. In this sentence, it refers to the space under the title.

So altına kısa bir not yazdım means I wrote a short note under it.

You can think of it as related to an understood phrase like başlığın altına = under the title.

Because -a/-e here shows direction or destination: the note was written to that place, meaning under it.

• altına = to under it / under it
• altında = under it in a static location sense

With verbs of movement or placement, Turkish often uses the dative:

• masaya koydum = I put it on the table
• altına yazdım = I wrote it underneath

So altına fits the idea of placing the note in that position.

Because Turkish often drops the subject pronoun when the verb already shows who the subject is.

Both verbs end in -dim / -dım, which show first person singular past:

• çizdim = I marked/drew
• yazdım = I wrote

So ben is unnecessary unless the speaker wants emphasis:

• Ben çizdim, ben yazdım = I did it, not someone else

They are in the simple past (also called the definite past) and mean completed actions.

Structure:

• verb stem + -DI past marker + personal ending

So:

• çiz-dim = I marked/drew
• yaz-dım = I wrote

The vowel changes because of vowel harmony, which is why one form is -dim and the other is -dım.

Its basic meaning is to draw or to make a line. But in context, it can also mean to mark, to underline, or something close to highlight.

With fosforlu kalem and başlık, the idea is that the title was marked with a highlighter. English may choose different verbs depending on context:

• I underlined the title
• I highlighted the title
• I marked the title

So the Turkish verb is broader, and context helps decide the best English translation.

Turkish word order is flexible, but the usual neutral pattern puts the verb at the end. This sentence follows that pattern.

Current order:

• Fosforlu kalemle başlığı çizdim, tükenmez kalemle de altına kısa bir not yazdım.

This order gives some emphasis to the tools used:

• first, with a highlighter
• then, with a ballpoint pen too

A different order is also possible, for example:

• Başlığı fosforlu kalemle çizdim, altına da tükenmez kalemle kısa bir not yazdım.

That would still be natural, but the focus shifts slightly.

They are both common Turkish expressions for types of pens.

• fosforlu kalem literally means something like fluorescent pen and is used for a highlighter
• tükenmez kalem literally means pen that does not run out, but in normal usage it means ballpoint pen

So even though the literal meanings are interesting, learners should treat them as standard vocabulary items.