To Place a Multi-Line

Select the Place Multi-line tool ( Drawing > Home > Multi-lines ).
Enter a data point to define the beginning of the multi-line.
Continue entering data points to define other vertices.
Do one of the following:

To complete an open multi-line, Reset.

or
To complete a closed multi-line, click the Close Element button or key in CLOSE ELEMENT.

In the latter case, the multi-line is closed at the location of the first vertex, and this vertex has a corner joint.

Left: Resetting after entering data point 4 to complete an open multi-line.

Right: Clicking the Close Element button after entering data point 4 to complete a closed multi-line.