Ci talk:1016663984
A "previewed movie" is a complete movie that one has previewed (e.g. by watching its trailer). Example: "Then, you decide if you want to go see the previewed movie when it comes out and begin to save your nickels so you can attend."
Or it can mean "a second-hand DVD or tape", as in "Previewed Movie Sale. $4.95 each or 3 for $10.00."
But 预告片 doesn't mean either of those things. It means "trailer": a short filmed advertisement for a movie, TV show, or video game.
预告片，指电影（片）或电子游戏未上映或未发行之前展出精华片段，目的是为该片做宣传。[1]
截取一部影片的若干精彩片段，而製成的宣傳短片。 [2]
But ABC's gloss "trailer (in a movie/TV)" doesn't seem to make sense. A trailer may be shown before the screening of a movie, but not in a movie. And certainly not "in a TV".