29. The field research will take Joan and Paul about five months; it will be a long time ______ we meet them again.
34.Take the lift to the eighth floor and turn right. You_______have any trouble finding my office.
33.The highway through the rain forest was completed in 1990, _________some animal species have died off.
32.With so many trees and flowers_____about, our school campus looks like a beautiful garden.
31._________reasonable, the idea he to create a friendly environment attracted much public attention.
30.We think that it’s love, generosity and perseverance______make the world it is today.