appearance 普通用词，着重由总体产生的印象。
look 普通用词，多用复数，可与appearance换用，但较口语化。
face 侧重指容貌。
aspect 书面用词，突出人或事物在某特定时间或地点时的外貌。
参考例句
1. Appearance: In powder with brown color. 外观：产品为棕褐色粉末。
2. Appearance: In powder with yellow color. 外观：产品为淡黄色粉末。
3. Appearance: In powder with lavender color. 外观：产品为淡紫色粉末。
英英解释
n.
1. outward or visible aspect of a person or thing
2. the event of coming into sight
3. formal attendance (in court or at a hearing) of a party in an action
4. a mental representation
5. the act of appearing in public view
6. pretending that something is the case in order to make a good impression
