What word can be used in one sentence five times in a row and still be grammatically correct?

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see: http://en.wikipedia.org/wiki/Buffalo_buffalo_Buffalo_buffalo_buffalo_buffalo_Buffalo_buffalo

The pub the the Horse and Groom was having its sign replaced. After the work had been done, the manager spotted a mistake. He rand the builders and said " The gaps between horse and and and and and groom are not the same distance"