OK, so I don't really understand this game.
The directional keys functionality makes it really hard to move and aim at the same time.
So I destroyed a ship, then went on to type the word. I was close enough to the word rock.
I typed directly, or am I not supposed to do that, am I to click something first?
I went closer to the rock, hit it, and it was immediately game over! Perhaps make it more forgiving.
Also, the audio effects. The explosion sound is too loud compared to the firing sound. Could give anyone a heart attack, so try to 'level' the sounds out so they are all around the same volume.
Also, use a different font, like on the buttons, the explanatory text, etc. Try make it look more professional.