Comparing teaser trailers from different genres - Introduction

When I analysed posters from different genres I noticed that they each shared certain design conventions. Now that I am looking at teaser trailers, I want to see if the same applies here. I am going to look at the teaser trailers for the following films:

1) Star Wars Episode VII - Science Fiction

2) Hunger Games: Mockingjay - Fantasy

3) The Expendables 3 - Action

4) The Dictator - Comedy

5) Noah - Epic

Even though the teaser trailers are from different genres, I think that there will be many conventions that they share, but  I want to double check this by analysing the teaser trailers closely. I am going to begin with the teaser trailer for Star Wars Episode VII.