A．He caught cold.
B．He ate rotten food.
C．He breathed in harmful chemical vapours.
D．He fell from his bicycle.

A．Lying in his bed.
B．Seeing the doctor.
C．Visiting his parents.
D．Delivering a lecture.

A．Knocking the air cushion overboard.
B．Putting out the sea anchor.
C．Diving into the sea to try to fetch the air cushion.
D．Putting out the sea anchor clumsily so that it became entangled.