Nothing takes me out of the flow of a story faster than an ill-constructed sentence. When I was reading the other evening, I came across a sentence with a double that in it. Now, even though double thats often are correct, especially when spoken, they are usually very awkward when read. I have had more than one English teacher in my past pound into my head that writing a sentence with a double that construction was just plain lazy writing and a rewrite was in order.

I think the problem is the word that can be so many different parts of speech.

• That can be a conjunction: It’s a matter of opinion that pitchers should ice their arms after every baseball game. (Correct.)
• That can be an adjective: Bring that pitcher some ice for his arm! (Correct.)
• It’s a matter of opinion that that pitcher actually needs to ice his arm after the baseball game. (Correct, but ill-constructed.)
• It’s a matter of opinion pitchers need to ice their arms after every baseball game. (Correct, but better.)

Now, that can also be an adverb and a pronoun, so be careful when constructing your sentences. When in doubt, read your sentence aloud. See if you even need that in the sentence.

More examples:

• That as a demonstrative pronoun (not following a noun) — Who gave you that?
• That as a relative pronoun (forms the subject, object, or complement or a relative clause) — Baseball’s a game that my mother taught me.
• That as an adverb (before an adverb or adjective) — I can’t wait that long.
• That as a determiner (followed by a noun) — Give me that bat.