Learn Turkish: Yatakta uzanmaktansa pencereden vadiyi izlemeliydin. - Instead of lying in bed, you should have watched the valley from the window.

It uses the structure -mAktAnsA, which means "rather than" or "instead of". It is built by taking the infinitive dictionary form of the verb (uzanmak), adding the ablative case (-tan), and finally adding the conditional suffix (-sa).

How do we get "you should have watched" from izlemeliydin?

This word combines the necessity suffix -meli (should/must) with the past tense -di. Breaking it down: izle (watch) + meli (should) + y (buffer) + di (past tense) + n (you). When you attach the past tense to -meli, it changes the meaning from "you should" to an unfulfilled past action: "you should have".

Why use the ablative case -den (from) in pencereden?

In English, you usually look "out of" or "through" a window, but in Turkish, the logic is that you look "from" it. Therefore, whenever you talk about looking out a window or a door, you use the ablative case, resulting in pencereden.

Why does the word vadi (valley) become vadiyi here?