系动词后接形容词作表语，常见的有感官系动词和变化系动词。
要点讲解
- be 系动词：He is happy. 他高兴。
- 感官系动词：look 看起来，feel 摸起来/感觉，sound 听起来，taste 尝起来，smell 闻起来——后接形容词：The food smells nice. 食物闻起来很香。
- 变化系动词：become/get/turn/grow 变得：The leaves turn yellow in autumn. 秋天树叶变黄。
- 保持系动词：keep/stay 保持：Keep quiet, please. 请保持安静。
- 感官系动词无被动语态、不用于进行时：不能说 The flower is smelt nice.
- look 系动词与 look at 实义动词的区别：She looks happy.（系动词+形容词）；She looks at the picture.（实义动词+宾语）
经典例句
- The silk feels soft and smooth.
丝绸摸起来柔软光滑。 - His voice sounds beautiful.
他的嗓音听起来很美。 - The days are getting longer.
白天越来越长了。
易错提醒
- 感官系动词+形容词是固定结构，接副词是错的：The soup tastes well 错误，应说 tastes good/delicious。