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 yesterdayThe 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。