It is important to have your eyes examined regularly to check for any sign of eye disease that may not have any ________.

. Seeing her daughter came home safe and sound, the mother felt at ______. 

Our manager has gone to Paris, so I have to deal with all the letters during his ________.

 It’s hard to imagine a large city without policemen, but such was the ______ in London in the early 18th century.

一I’we heard that another brand of milk powder has been banned .－It’s a shame that some companies lack the sense of social responsibility and       ．