Original sentence: A gutter on a roof usually rectangular in shape; may be lined with metal, asphalt, or roofing felt;may be concealed behind, a parapet, the eaves or in a roof valley.Box gutter, Parallel Gutter, Trough gutter
Edited sentence: A box gutter, parallel gutter, or trough gutter is a rain gutter on a roof usually rectangular in shape; it may be lined with metal, asphalt, or roofing felt, and may be concealed behind a parapet or the eaves, or in a roof valley