случилось много интересного за то в

случилось много интересного за то время, которое мы не обменивались письмами

Результаты (английский) 1:

many interesting things happened during the time that we don't have exchanged letters

Результаты (английский) 2:

many interesting things happened during the time that we did not exchange letters

Результаты (английский) 3:

happened many interesting things in the time which we exchanged letters