The interval between major earthquakes might be 200 years.

大地震之间的间隔时间可能有200年。

《牛津词典》

The interval may be assumed to have been a major formative period in his life: he was 21 years old when it began, 31 when it concluded.

但是这段时间可以被认为是一个人的成形时间(formative period)：开始于他21岁，终止于他31岁那年。

youdao

Larger by a semitone than the corresponding major or perfect interval.

比相应的大音程或完全音程增多一个。半音。的。

youdao

However the hours before the drama either side of the tea interval will be best forgotten by the tourists, with poor catching a major factor in the hosts' comfortable progress.

BBC: News | Cricket | Saqlain stars in Aussie collapse