Rules 4: Use Your Words
Many innocent words and phrases may be interpreted differently by different people. Even within a given context, meaning may not be clear. It's virtually impossible to avoid this completely, but at least be aware of your words, and learn to see all possible meanings.
If condition A occurred in the last round, score 2 bonus points.
Does "last" mean "previous" or "final"?
If there's a token at either end of the road, score it.
Does "either" mean "one or the other", or "both"?
In software, programmers are acutely aware of the difference between inclusive and exclusive "or". "A inclusive or B" means A or B or (A and B). "A exclusive or B" means A or B, but not both. So what does the simple use of the word "or" mean in game rules without further qualification? Do you think you could come up with a rule to its interpretation? Try it, then try to apply it to these two sentences:
On his turn, a player takes action A or action B.
The game ends if condition A or condition B occurs.
Instinctively, you will likely assume the first "or" is exclusive, and the second inclusive.