Sorry, but you are working with a *w*o*r*d* processing program, not a
graphic design program. Despite the array of drawing tools that are provided
there are limitations to what can be done with them - IOW, the vector shapes
can't be "partially" erased. You can try using the various pen/line tools
(which vary depending on which version of Word) to create your own
illustrations & there are ways to "fake it" but the result will most likely
not be what you want & may be more of a headache than you think
Do your artwork in a program designed for that purpose, then Insert it into
your doc as a finished product.
Regards |:>)
Bob Jones
[MVP] Office:Mac