请问一般过去时肯定有表示过去的时间状语吗?

可以有
I saw a film yesterday
The factory was built in 1980
也可以没有,这要看语境,上下文了.
Oh,it is you!I didn't know you were here.
哦,你在这呀!我不知道你在这.
A:I won't go there with you.
B:But you promised.