Williams 's songs include hits for Three Dog Night ( `` An Old Fashioned Love Song '' , `` Family of Man '' , `` Out in the Country '' ) , Helen Reddy ( `` You and Me Against the World '' ) , and the Carpenters ( `` Rainy Days and Mondays , '' `` I Wo n't Last a Day Without You , '' and `` We 've Only Just Begun '' ) . Williams is responsible for a number of enduring pop hits from the 1970s , including several hits for Three Dog Night ( such as `` An Old Fashioned Love Song '' , `` The Family of Man '' , and `` Out in the Country '' ) , Helen Reddy ( `` You and Me Against the World '' ) , and The Carpenters , most notably `` Rainy Days and Mondays , '' `` I Wo n't Last a Day Without You , '' and `` We 've Only Just Begun '' , which has since become a cover-band standard and de rigueur for weddings throughout North America .