This truncated diagram provides an example of how to read the solid red relationship lines to move in one direction:

The first class specification is diagram.

The second is that contain symbols.

The third relation/class specification is defined by definitions.

The fourth relation/class specification (assuming a global model) is uses definitions.

The fifth and last relation/class specification is that are instances of (is a) definition.

When writing a report, you must pick an object (like a diagram) as a starting point and travel only in the direction indicated by the arrows, always staying with the same color line. Therefore, if you travel along a red arrow, you cannot specify a relation between objects that are displayed on a line ending with a blue arrow.