Bu ağaç geçen yıl öldü.

Bu means this when it comes before a noun. So bu ağaç means this tree.

By itself, bu can also mean this or this one. In contrast, Turkish often uses şu or o for that, depending on the situation.

Turkish does not have articles that work like English the and a/an.

So instead of saying something like the tree or a tree with a separate article, Turkish usually leaves the noun bare and lets context show the meaning. In this sentence, bu already makes the noun specific, so bu ağaç naturally means this tree.

Yıl means year.

Geçen comes from the verb geçmek, which means to pass. So geçen yıl literally means the year that passed, and this is the normal Turkish expression for last year.

Öldü is in the simple past tense, often called the -DI past in Turkish grammar.

It is used for completed actions or events in the past. So here it means died.

The dictionary form is ölmek, which means to die.

To form öldü:

• start with the stem öl-
• add the past tense ending
• the result is öldü

So:

ölmek → öl- → öldü

The Turkish past tense ending changes shape depending on two things:

1. vowel harmony
2. whether the sound before it is voiced or voiceless

The past tense suffix has several forms:

-dı, -di, -du, -dü, -tı, -ti, -tu, -tü

In öl-:

• the last vowel is ö, which is a front rounded vowel
• that makes the suffix vowel become ü
• the final consonant l is voiced, so the suffix uses d, not t

So the correct form is öl + dü = öldü.

Because ağaç is the subject of the sentence.

In Turkish, the subject is usually in the basic form, called the nominative, and this form normally has no ending. So ağaç stays just ağaç.

Not completely.

The most neutral Turkish word order often puts the verb at the end, so Bu ağaç geçen yıl öldü sounds very natural.

But Turkish allows some flexibility. For example:

Geçen yıl bu ağaç öldü.

This still means the same thing, but the emphasis shifts a little. The version with geçen yıl first puts more focus on the time.

Yes. Ölmek can be used for a tree, plant, or other living thing dying.

So Bu ağaç geçen yıl öldü is a normal sentence.

Depending on context, Turkish may also use verbs like kurumak for dry up / wither, especially for plants. But ölmek is absolutely possible here.

The word ağaç is pronounced roughly like aa-ach.

The letter ğ in modern Turkish usually does not sound like a hard English g. In many words, it mainly lengthens the vowel before it or creates a smooth transition between vowels.

So in ağaç, you should not pronounce a strong g sound. Think of it more like a longer a sound before aç.

No. Turkish does not need a separate subject pronoun here because the subject is already stated: bu ağaç.

English needs it died, but Turkish can simply say bu ağaç öldü. Once the noun is there, no extra pronoun is necessary.