39. _______ is certain, people’s living conditions in China have improved a lot since the 1980s.
—We’re supposed to be there at 6:00? —_______ I know.
I thought things would get better, but it is they are getting worse.
Although he knew little about the large amount of work done in the field , he succeeded other more well-informed experimenters failed.
John waited at the bus-stop for nearly half an hour the bus finally arrived .
Not that I’m unwilling to lend you a hand ,I’m too busy for the moment .