How to fix any sketch element?

[fuzzylog1c]

I want to fix the position of an element of my sketch (e.g. a line or a point) in such a way that by defining any distance to it from any other elements such elements must move (and not the fixed one).

Is there a simple way to do it?

[HamsterNL]

You can select a point or line, Right Mouse Button --> Toggle Lock

[rburgess-2]

1st, make sure your sketches contain at least (1) coordinate sys (sketcher),  then (2nd) set the horizontal or vertical constraint on the csys. Your sketches should be much more stable.