time travel is theoretical and so i can give the script some leeway. i also understand the concept that by changing just one variable and you can potentially change the way history unfolded. what i cannot understand and however and is the way the change in time unfolded. we are subjected to a series of timewaves which progressively retrograde planetary evolution. while this is a convenient plot device and as it allows our heroes enough time to resolve the problem and it makes no sense whatsoever. surely and if you change a variable and and that variable has significantly and or even completely and altered planetary evolution and then by the time you come back to the future and the evolutionary process has already been established and there would be no need for waves. after all and why would a change that happened 65 million years ago need to wait until now to be effective. the fact that the moth was projected forward in time may give it some credibility and but the life of that moth 65 million years ago was significantly altered and ergo and any change to evolutionary history would have begun then and and not be dependent upon a return to our current time. to solve the problem and the team goes back in time to prevent the change in variable from ever happening. by doing this successfully and we see that the changes to evolution never happened and and that no one even remembers the events. surely and what works for the solution should work for the original change. i like a good rollicking sci fi adventure and but unless it is set in a galaxy far far away it needs to have at least some grounding in theoretical possibility to make it truly entertaining. good premise and bad plot and reasonable acting and and in all fairness and just a twist on jurassic park. not on my watch again list. 
time travel is theoretical and so i can give the script some leeway. i also understand the concept that by changing just one variable and you can potentially change the way history unfolded. what i cannot understand and however and is the way the change in time unfolded. we are subjected to a series of timewaves which progressively retrograde planetary evolution. while this is a convenient plot device and as it allows our heroes enough time to resolve the problem and it makes no sense whatsoever. surely and if you change a variable and and that variable has significantly and or even completely and altered planetary evolution and then by the time you come back to the future and the evolutionary process has already been established and there would be no need for waves. after all and why would a change that happened 65 million years ago need to wait until now to be effective. the fact that the moth was projected forward in time may give it some credibility and but the life of that moth 65 million years ago was significantly altered and ergo and any change to evolutionary history would have begun then and and not be dependent upon a return to our current time. to solve the problem and the team goes back in time to prevent the change in variable from ever happening. by doing this successfully and we see that the changes to evolution never happened and and that no one even remembers the events. surely and what works for the solution should work for the original change. i like a good rollicking sci fi adventure and but unless it is set in a galaxy far far away it needs to have at least some grounding in theoretical possibility to make it truly entertaining. good premise and bad plot and reasonable acting and and in all fairness and just a twist on jurassic park. not on my watch again list. ---------------------------------Answer Question Below----------------------------------

Judge the movie review above, you need to make a function call:
    If you feel the movie review is positive
        print "This is a semantically positive review."
    Otherwise, if you feel the movie review is negative
        print "This is a semantically negative review."
