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Hi Oxygenretreat, Singulars and plurals should be treated the same, so your main page should be targeting both "exotic vacations" and "exotic vacation" because Google sees them as the same in most instances.  As for internal linking, it doesn't hold near the weight with Google as it has in the past.  My suggestion would be to make sure that your anchor text is related to the page and thats about it.  If you have a page about exotic vacations make sure that the internal anchor text links to it with some form of exotic vacations and not some term like "home".  Since internal anchor text is easily manipulated Google has reduced it's role in their ranking models over the past years. Casey