是定语从句,先行词是last night
He came when I was out这个才是时间状语从句,找不到先行词
【【判断定语从句和时间状语从句从句的方法
定语从句与时间语状语从句的区别
当定语从句的引导词与时间状语的连接词都是when时,定语从句修饰、限制、说明时间名词,只能放在先行词的后面；而时间状语从句说明动作发生的情况,并且可以放在主句的前面.如：
Do you know the time when the class is over?你知道下课的时间吗?(定语从句)
It was already five o’clock when the class was over.—When the class was over,it was already five o'clock.当课结束时,已经是五点钟了.(时间状语从句) 】】】
就像这句
不能说成when I was out,he came last night .所以你说时间状语从句.