I find that Japanese is a weird language for its learners, especially for those who've already learned English. In English one usually uses two tenses: present and past, however in Japanese there are accomplished and unaccomplished tenses, and these look strange if literally translated to English. For instance:
Literally "When I go to Japan, I bought a radio."
Here, the English sentence has two different parts which use two unrelated different tenses, so it's obviously logically wrong.
Literally "When I went to Japan, I decide to buy a TV made in Japan."
And this sentence also sounds strange.
Can anyone explain how to think about Japanese tenses for sentences like these? I'm really puzzled by it.