Sometimes passengers can upgrade their class for free.( )
举一反三
- Sally can upgrade her anti-virus software for free.
- Bar service is offered to both first class and economy class passengers for free.
- Bar service is offered to both first class and economy class passengers for free. A: 正确 B: 错误
- 中国大学MOOC: Business class passengers are allowed to check 40 kilos of baggage for free.
- Business class passengers are allowed to check 40 kilos of baggage for free. A: 正确 B: 错误