common 多用于指物，侧重很常见，不稀奇。
ordinary 用于物，指每天发生，十分平淡无奇；用于人，指无特别之处，很一般。
common place强调缺少新意。
general 语气强于common，侧重大多如此，很少有例外情况。
usual 指常见常闻和常做的事或举动，强调惯常性。
popular 指适应大众爱好、需要，为大家所公认或接受。
universal 与general同义，但语气较强，侧重对每个人或事物都适用，根本没有例外。
参考例句
1. We all have a common home. 我们拥有一个共同的家。
2. This is the pathogenesis common to all symptoms. 这便是诸多症状共同的发病机理。
3. The following explanations define the most common applications. 下列的解释定义了最常见的应用。
英英解释
n.
1. a piece of open land for recreational use in an urban area
2. belonging to or participated in by a community as a whole; public
3. having no special distinction or quality; widely known or commonly encountered; average or ordinary
4. common to or shared by two or more parties
5. commonly encountered
6. being or characteristic of or appropriate to everyday language
7. of or associated with the great masses of people
8. of low or inferior quality or value
9. lacking refinement or cultivation or taste
10. to be expected; standard
