1. Zebras are MORE vicious COMPARED TO horses.
2.WHEN COMPARED TO horses,zebras are vicious.
Can anyone explain why these sentences are wrong ? Thanks
1. There are some things about idioms that you just need to memorize. This is just not appropriate. You are better off writing -> Zebras are more vicious THAN horses.
2. As compared with (or to) horses, zebras are vicious. Note that the GMAT doesn't really emphasize the difference between compared with and to.