No one expected house prices to fall, but _____ that's exactly what happened.

----- I am certain David has told you his business troubles. ----- ______, it is no secret that he owes a lot of money to the bank. 

When asked why he prefers bikes to buses, the professor said,  “Riding a bicycle takes __________ half an hour, but it’s more convenient and environmentally friendly. ”

Progress so far has been very good.______，we are sure that the project will be completed on time.

 Honestly speaking, I would agree with Cathy, though not __________.