1. 结构
现在进行时 = be + 动词现在分词(V-ing)
- I am working.
- She is reading.
- They are studying.
2. be 动词作用
- 系动词:I am a teacher.
- 助动词:在进行时中承担时态与人称变化。
3. -ing 变化规则
- 直接加
-ing: look -> looking - 词尾
e去掉再加-ing: write -> writing - 辅元辅结尾双写尾字母再加
-ing: hit -> hitting - 词尾
ie变y再加-ing: die -> dying
4. 对比例句
- I eat apples.(习惯)
- I am eating an apple.(此刻正在发生)