Logical Fallacies.

I can drink beer even though I am underage because everyone else under twenty one is doing it.

This is an example of a bandwagon appeal because this person is assuming that everyone else out there is drinking underage, therefore it is okay if they do it too.  In reality, not everyone underage in the world is actually drinking beer; it might just be the case that everyone they hang around or come in contact too on the weekends is partaking in these events.  Just because this is the case, doesn’t mean it is the truth, it just makes the idea more appealing.

I would have finished cleaning the house if the weather wasn’t so nice outside.

This is an example of a rationalization.  This is a very weak explanation as to why the house didn’t get cleaned.  Regardless of whether it was nice outside or not, the house would have just as good of a chance to get cleaned. It didn’t just because of the simple fact that you wanted to spend more time outdoors.

We have had extreme weather the past few years. This is a sure sign of global warming.

This is a hasty generalization.  This is a very broad statement, when in reality; there could be numerous other reasons as to why the weather is behaving the way it is.  It would take a very, very long time to be able to track the trends of the weather patterns.  A simple generalization would not do the trick.