Needs a little context to get the answer you want, I suspect. Bend a pipe - ok curve a pipe - ok, but never heard it. . There is a bend in this pipe - ok There is a curve on this pipe - ok, but a little unusual . Bend the knee - ok curve the knee? - nope - Some things bend at a point, like knees, elbows, curve is gentle, not abupt, so bend works some places that curve does not. . Bend it till it breaks - ok Curve it till it breaks - strange as curve generally means shape, smoothly. . The road has a gentle bend to the left just after the bridge. The road has a gentle curve to the left just after the bridge. . The road bends left - strange The road curves left - ok . She had curves where she should have curves - ok, informal She had bends where she should have bends - cannot picture it as a good thing She had bends where she should have curves - Sounds bad . Head torwards the corner post, then curve round towards the goal - ok Head torwards the corner post, then bend round towards the goal - strange . I know it is bending the rules a little, but we will do it anyway - ok ("bend" comes before "break") Never heard of curving the rules :( ("curve" is not associated with "break") . The car left the road at the bend after the summit. - ok The car left the road at the curve after the summit. - ok