中国大学MOOC: Penicillin was discovered by accident in the summer of 1928.
举一反三
- Like<br/>some other discoveries, Penicillin was discovered quite( ) A: by accident B: in event C: at incident D: as accent
- 中国大学MOOC: Who discovered X-rays?
- 中国大学MOOC: It was believed that America was first discovered by ____________.
- 中国大学MOOC: was believed to have discovered America.
- 中国大学MOOC: The Terracotta Warriors were discovered when ________.