Parallel Constraint
- Select Drafting | Constraints |  Add parallel constraint. Add parallel constraint.
- Select two lines.

 Select line elements, and then select the Constraints > Parallel function from the context-sensitive menu.
 Select line elements, and then select the Constraints > Parallel function from the context-sensitive menu.
Note: 
      
  - If you add a line parallel to another line by pressing the E key, parallel constraint is created automatically.
