11.   Because negotiations had been going on since March, the city was not caught unawares.

12.   Besides, a lot of fast horses have come and gone since Bert Coan.

13.   A quarter of a century has gone by since the end of the war, since that glorious morning of victory.

14.   A lot of time has gone by since then.

15.   Actually, this revamping has been going on since last year.

16.   But a lot of Christmases have gone by since the recession.

17.   But it was a token gesture, and the Americans have not gone back since.

18.   Complaints against police have gone down since the program started, Parks said.

19.   Discussions between Apple and Sun have been well documented and have been going on since last September.

20.   Debates have gone on since then as to whether the same-sex union ban is advisory or mandatory.