ナントカは昔のことだと言いたい時に使います。0:39 Gone are the days when they were under-equipped and badly trained. 
http://www.youtube.com/watch?v=sJ1s5tSgQ54 0:03 Gone are the days when slathering on baby oil and lying in the sun for hours was acceptable, even normal. ベビーオイルをべっとり塗って何時間も日光浴できたのは昔のこと
http://www.youtube.com/watch?v=CjRPqF4KV_s 0:22 Gone are the days decades ago when unions were given the nod by society and one in every three American workers belonged to one. 労働人口の三分の一が組合に加盟していて組合が社会の支持を受けていたのははるか昔の話。
http://www.youtube.com/watch?v=Unngwljxdrs 4:45 gone are the days when people earned enough here to put down their deposits to buy somewhere.物件を買うのに保証金を払えた日々は昔のことだ。
http://www.youtube.com/watch?v=6CpN8LSZbvo  3:36 gone are the days of lying in bed and eating for two. 産後にゆっくりと養生して栄養のあるものを食べるのは昔の話になった。
                                        
練習問題解答
                                        
a-4130    gone are the days of
                                        
a-4323    gone are the days when
                                        
a-9668         gone are
                                 
b-3006  gone are the days when
                                 
b-4346         gone are the days of