✔ 最佳答案
i would suggest you to visit some museum's site and click one some art pieces for examples. (not all pic has criticise)
such as:
http://www.metmuseum.org/home.asp
http://www.louvre.fr/llv/commun/home_flash.jsp?bmLocale=en
i think you can say sth like:
1. the color : ex. what colors? the variety of color? change within the same color?
2. shadow : ex. how the color change? where is the light? where is the shade? how the artist change the shade? by black pigment? or by adding other color?
3. the organization of the whole pic : what's included? how they are arranged?
4. any meaning behind the pic?
5. your own impression : ex calm, peaceful.. ... ... make some objective comment but also subjective.
good luck on yr paper~