What will people die of in 100 years? If you think that is a simple question, you ______ attention to the revolution taking place in biotechnology.
A．have not been paying B．had not been paying
C．were not paying D．will not be paying
The government has taken some measures to solve the shortage of electricity, but it may be some time _________ the situation improves.
A．since B．when C．before D．unless
Mandela, having devoted all his life to the freedom of South African Blacks, is a real fighter for us to_________.
A．live up to B．come up to C．make up to D．look up to
You cannot imagine what great trouble I took ______ your house.
A．to find B．finding C．found D．having found
Jordan kept his illness from his opponents before the final game ________ they might know about it.
A．now that B．on condition that C．for fear that D．in order that
— Have you seen ____ pencil? I left it here this morning.
—Is it _____black one? I think I saw it somewhere.
A．a; the B．the; the C．the; a D．a; a
