How many years would a patent be protected?
20
举一反三
内容
- 0
How many years had Rip been asleep?( ) A: twenty years B: ten years C: fifteen years D: thirty years
- 1
How many years has the company been operating A: 15 years B: 20 years C: 25 years D: 30 years
- 2
How many years has Lang been playing clarinet?
- 3
How many years must a British student study in the university?
- 4
How many piece of (bread) would you like?