One of my teachers says that there is no such thing as "absolute truth". Could
Philosophers disagree about this, but I think there is such a thing as absolute truth.
We need to distinguish the question of truth from the question of knowledge. It may well be there there is no such thing as 'absolutely certain knowledge', something we believe to be true and that we couldn't possibly be wrong about. But whether we can know an absolute truth for certain or not, there could be such a truth.
We need to allow that there may be certain statements that are not absolutely true or absolutely false, because they do not have a crisp enough meaning. One way this might happen is if one of the words in the statement is vague. So, it may be that a statement like 'People with exactly 100 hairs on their head are bald' is neither absolutely true nor absolutely false. But it doesn't follow from this that there are no absolute truths, because it doesn't follow that every statement uses vague words.
There may be some areas where absolute truth is not to be had. Some people would say this about statements about ethics, others would say this about statements about beauty. But it doesn't follow that there are no areas where there is absolute truth.
So does this leave any a plausible examples of an absolute truth? Here is one: 'There are trees in Oregon'. Not the most exciting statement, but it's true, and not just for me. It's just true, absolutely. I leave it to you to come up with more interesting examples.