单项选择题
A．dumb B．establish C．debt D．doubtful
A．The teachers did lots of writing on the board. B．The teachers were invited to attend several lectures. C．The students were professors from a university. D．The students were studying science and humanities.
A．how to hunt whales for their oil and meat B．the hard and dangerous lives that whalers had to live C．the duties of each man on a whaling ship D．a man who was swallowed by a whale and lived