ずっと: for a long time

彼女かのじょとはずっと前まえから友ともだちだ。

She and I have been friends for a long time.

そのため、今いまの人ひとより、寿命じゅみょうはずっと短みじかかったと考かんがえられています。

For that reason, it is thought that their life expectancy was much shorter than that of people today.