Free course
现在完成进行时
What has been happening — and has not stopped.
Robert & Theo · 中级 · 语法
现在完成进行时
Robert和Theo教授现在完成进行时：have been + -ing，for和since，以及它与I have done和I am doing的区别。免费口语语法课程。
What you get
- This course is free — sign in to keep your place
- 8 spoken lessons with Robert and Theo
- 2 practice pages — Robert reads the questions
- Replay every lesson as often as you like
Sign in to save where you stopped. The lessons stay free.