An image-forming machine comprising a conveying passage (51) for conveying a sheet material through a transfer zone, a first (66) and a second (68) feed means for feeding the sheet material to the conveying passage (51), a first feed passage (86) for conducting the sheet material delivered from the first feed means (66) to the conveying passage (51), a second feed passage (96) for conducting the sheet material delivered from the second feed means (68) to the conveying passage (51), and a first (124) and a second (126) opening-closing member for opening and closing the first and second feed passages. Various improvements are made on the first (124) and second (126) opening-closing members. Further provided are an improvement for suppressing noises, an improvement for preventing folding of a sheet material, an improvement for easily switching over to a mode of forming an image on both surfaces of a sheet material, an improvement for accurately conducting the sheet material from a reversal holding portion (382) to a return passage (384), and an improvement for positioning the sheet material received in the receiving-refeeding means (386) at a predetermined widthwise position in the above and other types of image-forming machines.