I can't forget the time ( )the earth quake happened in yushu

I can't forget the time ( )the earth quake happened in yushu
I can't forget the time ( )the earth quake happened in yushu

I can't forget the time ( )the earth quake happened in yushu
when=in which
为定语从句,缺少介词所以用in which,又可以用when

when
因为是在那个时间，when做时间状语。加油哦！

填 when
引导定语从句，表示时间。

when

关系副词做时间状语。因不及物动词happy 后不能接宾语。填when