中国大学MOOC: Pilotless flight safety and security are what pilots are concerned about.
举一反三
- Pilotless flight safety and security are what pilots are concerned about. A: 正确 B: 错误
- 中国大学MOOC:"Graph should have a ____ to explain what it is about.";
- 14. What is the man concerned about? A: The safety of weight-lifting. B: The high membership fee. C: The renewal of his membership. D: The operation of fitness equipment.
- 中国大学MOOC: While we try to teach our children all about life, our children teach us what life is all about.
- 中国大学MOOC: What attitude should security staff have whenconducting security check?