_____ a lot of small ads are put up on the walls, out city will be untidy.

Although he is very old, _________ he works very hard.

A cat, ______ it is a white one ______ a black one, is considered to be a good cat as long as it can catch mice. 

---Your Japanese is so good. How long have you been in France? --- __________ I was five.

  --  _______exciting news! --Yes, the 12-year-old boy in Beiingwas saved after the successful heart transplant.