1) We were talking for some time when the bell rang. 2). That day the Sun had been shining since morning and the sky was blue. 3). I told him what I have done and he had told me what he had been doing in the last three months. 4). They had been walking along the street for half an hour before they saw a cafe. 5). I was having breakfast when the telephone rang. 6). How long had you been knowing Mike before you got married? 7). She had been cooking dinner for half an hour when she remembered that she had run out of bread. 9). She thanked me for what I have done. 10). The children had been cleaning the front step for more than an hour before their mother called them to dinner. 11). The front step looked very clean after the children had scrubbed it. 12). The family was watching TV when I came home.