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.
In a family, ______ really works is ____ there is one person who understands the finances and takes care of it.
After decades of effort, the city is still trying to _____ how to ban smoking in public places.
It was on ________ Saturday in _______ July of 2009 that the famous scholar of Chinese traditional culture, Ji Xianlin, passed away.
When she was doing the cleaning yesterday, Mum found the ring that she _____ years ago.
--- Was he sorry for what he'd done? --- _____________.