Learning to differentiate the subtle nuances between 〜ている, 〜てある, and 〜ておく might be one of the biggest headaches for Japanese learners. The good news is that 〜ている, 〜てある, and 〜ておく aren't always interchangeable. The Basic Concepts of 〜ている, 〜てある, and 〜ておくLet's begin by comparing the basic concepts of 〜ている, 〜てある, and 〜ておく. Now let's finally get into the comparisons of the three patterns: 〜ている, 〜てある, and 〜ておく. situation-focused ⇔ action-focused てある ている ておくHere's an example to elaborate on what this means.