Students always keep candles in their rooms ______ there is a power cut.

A．Mrs. Andrews telephoned her husband because she thought that the sausages contained bad meat.
B．The dog was ill because the sausage it ate contained bad meat.
C．Jim was ill too, and he needed some medicine.
D．Mrs. Andrews telephoned her husband because she was worried about the dog.

A．The Keyling which sailed around the tip of the Cape of Good Hope came to London only by accident.
B．The world measures less than 30,000 miles in circumference.
C．The Cape of Good Hope is at the southern tip of Australia.
D．Today many Londoners still believe that many Chinese ships are not seaworthy.