【題目】Scientists say it will be five or six years ________ it is possible to test this medicine on humans．

【題目】It is wise to have some money ________ for old age.

【題目】People who do not smoke have less ________ of suffering from lung cancer than those who do so.

【題目】The speech was wonderful ______ it lasted too long．

【題目】The living room is clean and tidy, ________ a dining table already laid for a meal to be cooked．

【題目】-- I am afraid I can’t help you with your project. I ________ a model these days.

【題目】The old castle requires ________ after ________ by the storm.

【題目】It was in the forest _____ they found the lost cow.

【題目】Facing the global financial crisis, the Chinese government has taken many measures ________ people's life to deal with it.

【題目】Common sense requires us to get away from the concept that national boundaries are frontiers _________ knowledge may not spread.