Trailer 2 Dawn of the planet of the apes

Dawn of the planet of the apes:

At the start of the trailer for dawn of the planet of the apes you hear synester music along with seeing destruction in a forest. This gives viewers an instant idea that there is war or some sort of fight and that there has been many tragedies. We then hear the voice of someone saying "we've been through hell together" which gives the impression that a fight has previously taken place.
After this we hear the voice again saying " we all know what we are up against" and straight after we see an image of an ape. This tells the audience that the humans are fighting against the apes.
For the next 20 seconds we see the image of the ape but the camera zooms outwards. As this is happening the music intensifies and as soon as the ape moves as well as all of the other apes the music reaches its highest point and then fades away to add drama to the audiences feelings.