The speech by the mayor of Shanghai before the final voting for EXPO 2010 is strongly impressed ___ my memory.

— Should people stop using their cars and start using public transport?— __________. The roads are too crowded as it is.

It remains________ whether Jim will be fit enough to play in the finals.

 Modern science has given ____clear evidence ____ smoking can lead to many diseases ____ it’s time for us to take measures.

 He had hardly reached home _______ an unexpected guest came to visit him.