The past tense of see is saw. As in, 'I saw it.'
However this usage is in decline. Now, everyone I see on television is saying, 'I seen it.' I haven't heard anyone say, 'I saw it up on the hill.' in years. Everyone 'seen' it up on the hill.
"It has been seen." is correct.
"I seen it." is technically incorrect. However, these days it is in common use.
This used to irk me a little, but I have accepted that 'seen' is the new 'saw'. Languages change over time. This just happens to be one that happened in my lifetime.
The same with, 'Where are you at?' Everybody says this. Even though it is ridiculous. 'Where are you?' is better. So many people are adding an extra word simply to make the question grammatically incorrect. 'at' in this case adds nothing to what is being said. And yet, everyone adds it. I don't know why.
Since we are on the topic, what is with replacing words that begin with vowels with 'uh'. For example, you never have to be there immediately, you have to be there 'uh'mediately. There is never an emergency. There is only an 'uh'mergency. Even newscasters, people who are supposedly trained in language do this. It is perplexing. There is no experiment. There is only an 'exspearmint'.
Oh well, life too short to worry about things like this.
Americans as a whole are pretty stupid compared to one or two generations ago. The disparity is even more obvious, I believe, if we go back 100 to 200 years.
Stupidity may very well be more contagious in our day of rapid mass communication. To illustrate: about two or three decades ago, I heard a TV news anchor warn viewers about an upcoming gruesome video clip by calling it "heart-wrenching." That was the first time in my life that I had heard anyone confuse "heart-
rending" with "gut-
wrenching."
(One can rend [rip or otherwise tear] a heart but not wrench [twist or knot] a heart.)
Several months later, I heard another TV anchor make the blunder of saying "heart-wrenching." By the end of the year, however, I was hearing the misstatement about once or twice a week--at both local and national news levels. My viewing habits were pretty constant at that time, and I don't believe the gruesome videos were becoming more common. The TV anchors were just getting dumbed down by their dumb colleagues in the media.
