Curve Edit > Create > Duplicate Curve Duplicates any curves that are picked when you click the tool, and any curves you click while the tool is active.
Curve Edit > Project Tangent Allows for the modification of a curve or surface edge to achieve tangency or curvature continuity with a surface, or tangency with a curve intersection.
Curve Edit > Curve Section Cuts, trims, or creates new geometry along a number of curves based on some criterion.
Curve Edit > Fit Curve Creates quality curves by fitting to cross-section line data, curves-on-surface, trim edges, isoparms (including surface edges and patch precision lines), and other free curves.