Conclusion

From watching different types of trailers from the same genre of Thriller, I have concluded that the conventions are mostly identical. Most Thriller trailers we be filmed in either a secluded or personal place (woods or a house), the lighting will be extremely dark, the music will be creepy and change from faster to slower to build tension.
The characters in each of the trailers weren't developed, however viewers can clearly see which is the antagonist and protagonist, many close ups are used in thrillers, this is to see reactions of the protagonist and the faces of the antagonist as if they are jumping out at the audience.
I have also seen that black screens are used a lot in each of the thriller trailers, this is to break up the shots and to create more tension and suspense for the audience.