—Why don’t you take some exercise? Sitting before the computer is bad for your health. ---________, but I have to finish my work on time.

________ her death in 1886, the poet had become a legend in her hometown. 

It is the first time I ____ to visit the Great Wall. 

The boy said ________ couldn’t he work out the problem but his teacher didn’t know how to do it.

--- “I’ve never eaten a hamburger.”--- “_________ have I.”