(1)要避免重复使用比较等级。如： [误]He is more better than before.http://yingyu.chazidian.com [正]He is much better than before. [正]He is better than before. (2)要避免将主语含在比较对象中。如： [误]China is larger than any country in Asia. [正]China is larger than any other country in Asia. (3)比较对像必须是同类可比较的。如： [误]Your computer is more expensive than Tom. [正]Your computer is more expensive than Tom’s. (4)最高级要注意将主语包括在比较范围内。如： [误]Tom is the tallest of his three brothers. [正]Tom is the tallest of the three brothers. (5)要注意定冠词在比较级中的使用。请比较： Which is larger, Canada or Australia? Which is the larger country, Canada or Australia? Tom is taller than his two brothers. Tom is the taller of the two brothers. (from http://yingyu.chazidian.com)