Premise: Two people are descending down some stone steps .
Correct statement: It is highly unlikely that two best friends enjoy the exercise .
Incorrect statement: There is a very good chance that two best friends enjoy the exercise .
Correct statement: Chances are about even that two adults are talking while walking down steps .
Incorrect statement: It is impossible that two adults are talking while walking down steps .
Correct statement: It is probably not the case that the people are male
Incorrect statement: It is likely that the people are male
Correct statement: It is probably not the case that two people are running down stone steps .
Incorrect statement: It is certain that two people are running down stone steps .
Correct statement: There is a very good chance that a couple of people are walking down the stairs outside .
Incorrect statement: It is impossible that a couple of people are walking down the stairs outside .