i'm sorry i disagree the explanation of shevelen8 totally. in my opinion 1、比is a preposition ,means than，ex.小王的性格比小李的性格好，the point is that xiaowang’s temperament is good,for accenting xiaowang's temperature we compare his temperature with xiaoli's. sth/sb+比+sth/sb+adj. maybe aslo is a verb in the sentence like that:不要和别人比。the 比 is short for 攀比。 2、比较：①verb,means compare,西安和成都比较起来，我更喜欢成都。compare xi'an with chengdu,i prefer chengdu.ex他正在比较不同水域的水质。he is comparing the water quality in different waters. A：sth/sb+sth/sb+比较+complement（起来，一下）B：比较+sth/sb+sth/sb ②adv. be put in front of adj. means less than adj.比较好<好<很好/ 比较急<急<很急 /比较漂亮<漂亮<很漂亮 --------------------------------------------------------------------------------------------------------------------------------- besides that 比 also means measure in dialects，这件衣服是比着他的身材做的。this clothes is made after measuring his size.

比 has lots of meanings, 比 can be a verb（动）, an adj（形）, an adv（副词）， a noun（名词），even a prep(介词），i suggest u to have a look at (http://xh.5156edu.com/html3/10580.html) it's the dictionary of XIN HUA on line, many of the meanings on it u may cannot understand, but u can see some English words to explain the Chinese , for example"比较;考校,核对〖compare;contrast〗比拟〖drawananalogy;likento〗 " i think those words can help u understand the Chinese well About 比较 ：to compare;rather;to contrast;relatively；compare with；和..比较 in comparison with In some ways 比 and 比较 are similar, but the meaning of 比 is much more widely than 比较 And I'm busying study Spanish now,,,, so my English may not good as it should be,,, Good luck

比 is short of 比较?