Rashi on Deuteronomy 4:10/רש"י על דברים ד׳:י׳

1יום אשר עמדת THE DAY THAT THOU STOODEST — This is to be connected with the preceding verse thus: [The things] which thine eyes saw … on the day that thou stoodest … at Horeb, — where thou didst perceive the thunder and lightning.

2יִלְמְדוּן — The Targum is יֵלְפוּן, “They shall learn" (more lit., the action reverts to themselves), while —

3יְלַמֵּדוּן the Targum is יְאַלְפוּן, “They shall teach" (more lit., the action reverts to others).