This machine _______. It hasn’t worked for years.
举一反三
- You can't use the machine because it hasn't been _____(test) yet.
- This is so difficult a problem that the scientist is known to ______ on it for about ten years, but hasn't found an answer yet. A: have worked B: have been working C: be working D: work on
- I haven't seen him for years. = It's years ____________________________.
- It's years ..................................................(=I haven't seen him for years.)
- According to the text, Linda is 19 years old and she hasn't had a steady boyfriend yet.