How do you know when to use ''de'' or ''da'' in Turkish?

In Turkish, the words ''de'' and ''da'' are used to indicate location, and they are equivalents to the English prepositions ''in'' and ''at''. The rule for using ''de'' or ''da'' is based on the vowel harmony principle, which means that the choice between ''de'' and ''da'' depends on the last vowel of the word that precedes it.

If the last vowel of the preceding word is a front vowel (e, i, ö, ü), you use ''de''. If the last vowel is a back vowel (a, ı, o, u), you use ''da''.

For example, you would say ''evde'' (in the house) because ''ev'' (house) ends in a front vowel, and ''oda'' (in the room) because ''oda'' (room) ends in a back vowel.

However, there are some exceptions to this rule, and some words do not follow the vowel harmony principle. In these cases, you need to memorize the correct form of ''de'' or ''da''.

The Turkish particles "de" and "da" are used to indicate location, time, and possession. They are pronounced the same way, but the spelling changes depending on the last vowel of the word they are attached to. If the last vowel is a front vowel (a, e, ı, i), the particle is spelled "de." If the last vowel is a back vowel (o, u, ö, ü), the particle is spelled "da."

Here are some examples of how "de" and "da" are used to indicate location:

• Evdeyim. (I am at home.)
• Okulda değilim. (I am not at school.)
• Bahçede oynuyor. (He is playing in the garden.)

Here are some examples of how "de" and "da" are used to indicate time:

• Bugün evdeyim. (I am at home today.)
• Yarın okulda olacağım. (I will be at school tomorrow.)
• Geçen hafta bahçede oynadık. (We played in the garden last week.)

Here are some examples of how "de" and "da" are used to indicate possession:

• Bu benim kalemim. (This is my pencil.)
• Araba senin mi? (Is the car yours?)
• Kitabı ona verdim. (I gave the book to him.)

It is important to note that the particles "de" and "da" can also be used to mean "also" or "too." In this case, they are not attached to a noun, but are written separately. For example:

• Ben de geliyorum. (I am coming too.)
• Sen de mi? (You too?)
• O da gelmek istiyor. (He wants to come too.)