I'm not a native English speaker, but I have many English friends. So in conversations I always short of quick but formal answers or exclamations in a sad situation. Like; Yesterday a strong tornado struck Oklahoma taking many human lives. I was talking with my friend about this tornado and he's telling me about the danger and its magnitude and also his close friend and a relative was just a few miles away from this storm, but I didn't know what to reply for this sentence. I simply said "Oh my God!". So therefore I need different expressions for these kind of situations.