Ben yazıcıyı bilgisayara bağlıyorum.

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Breakdown of Ben yazıcıyı bilgisayara bağlıyorum.

• bilgisayar: the computer
• yazıcı: the printer
• bağlamak: to connect

Questions & Answers about Ben yazıcıyı bilgisayara bağlıyorum.

Why does yazıcı become yazıcıyı?

Because you’re marking yazıcı as a definite direct object. In Turkish, specific/definite objects take the accusative suffix -ı/-i/-u/-ü. Here:

1. yazıcı (printer)
2. add the buffer consonant y (because the word ends in a vowel)
3. add the accusative -ı
   → yazıcı
   • y
     • ı = yazıcıyı (“the printer”).

Why is bilgisayara in the “-a” form?

That’s the dative case (“to/into”). The verb bağlamak (“to connect”) takes its target in the dative. You form the dative by adding -a/-e to a noun (vowel-harmonized). So:
bilgisayar + a → bilgisayara = “to the computer.”

What tense/mood is bağlıyorum, and how is it formed?