When can I omit a redundant 'that'? [duplicate]

Have you ever had a case where you felt compelled to include strange things like a double that in a sentence? If so, then what did you do to resolve this?

For me, I never knew whether it was acceptable grammar. However, what I did learn was that it was a logic distractor, could lead to confusion, and therefore should be reworded to avoid this.

Solution 1:

There are three very different uses of that:

• Subordinating that: “I know that this is the answer.”
• Demonstrative pronoun that: “That is not the answer.”
• Adjectival that: “That answer is not it.”

Double that occurs because the first that is the subordinating that, and the second that is a demonstrative pronoun or adjectival that. That is, if you subordinate a clause that begins with pronominal or adjectival that with that, you get that that, as in “you know that that that that from the previous sentence was different from the one in this sentence.”

Solution 2:

Of course it is acceptable grammar. The rules of English grammar are the very reason why such "strange things" happen in the first place.

Now, whether or not you actually end up using a double "that" or rewording it, is a different question. But it is a question of style. Read: personal preference.

Personally, more often than not, I don't find a double "that" to be distracting or leading to confusion at all. Quite the contrary: it is a) perfectly self-explanatory and b) it certainly leads to less confusion than leaving one of those "that"s out.

Solution 3:

I don't think that that is a problem.

Having said that, it would still make sense if one of the "that"s in the previous sentence were omitted.

EDIT: In response to Reg's comment:

If a "that" is omitted, it's the first one that is removed. Replacing the second "that" with "it" may clarify things:

I don't think that it is a problem.

I don't think it is a problem.

Hence saying "I don't think that is a problem" is fine - as long as you're familiar with this particular usage of the word "that". If not, then it could obviously cause confusion.