Break & Break at Point

Break

Break an object into two with gap

Home tab > Modify panel expand > Break

Select outer circle

Command Line: First point

Pick first point on top

Pick second point at below

For counter-clockwise rule
Circle break the small portion

Home tab > Modify panel expand > Break

Select inner circle

Command Line: First point

Pick first point at below

Pick second point on top

For counter-clockwise rule
Circle break the small portion

Break at Point

Break object into two without gap

Home tab > Modify panel expand > Break at Point

Select top line

Pick a point to break

Home tab > Modify panel expand > Break at Point

Select the bottom line

Pick a point to break

Home tab > Modify panel expand > Break at Point

Select the short line on top

Pick a point to break

Home tab > Modify panel expand > Break at Point

Select the bottom short line

Pick a point to break

Cross-select the 2 short lines

Select Hidden layer

Short lines displayed as dashed lines