I recently redoubled my efforts to read more. I have visited far too many sales lately and the piles of unread books are beginning to interfere with my desk and shelf space. So one night, I picked up a book and began reading.
I had gotten no further than one page into the preface when I came across this sentence: “I saw that the training and experience I had had in public speaking had been of more practical value to me… than everything else I studied in college.” A few pages later, another sentence stuck out to me: “However, let me warn you: you won't find anything new in it.” I still had not reached chapter one when a third sentence stopped me: “Because experience has taught her that that is the only way she can keep their provisions clearly in mind.”
Seeing repeated words being…well, repeated so often made me wonder whether the author did not notice or did not care to revise. The great majority of people will simply rework a sentence to avoid these awkward phrases, but is it truly improper grammar to repeat yourself?
In fact, it is exactly because of the rules of grammar that these word pairs need to exist. Words are flexible; a single word can often be used as several parts of speech and its meaning may even change based on how it’s used. Then there’s tense and subject and object and a myriad of other grammatical rules that alter the structure of our sentences.
Take the words had had; the second had is working as a past participle while the first had is a verb. Together, they create a Past Perfect verb. If the sentence were have had, this would be the Present Perfect tense. Because each had is operating as a separate part of speech, we must have both.
Still with me?
With the words you you, the first you is a direct object; the second you is the subject of a relative clause. While you may be tempted to punctuate between them, this is not always necessary. The words that that appear because the first that is a relative pronoun while the second that is a demonstrative pronoun. By now, you’re wishing you’d paid more attention to sentence diagramming in grade school, but don’t worry, I had to look all of this up too.
In summary, the same word can be used for different parts of speech and so it can appear back-to-back in a sentence and be completely grammatically correct. If you want to reword a sentence, go for it, but you don’t actually have to so why bother?