First, check for proper nouns. "I" is a pronoun, not a proper noun. "can’t" is a contraction. "help" is a verb, not proper. "with" preposition. "that" determiner/pronoun. No proper nouns. Therefore, all words should be replaced.

So, let's try that.

Next, for each word that isn't a proper noun, I need to find three suitable synonyms or variants. The example uses "help", "assist", "support" for "help", and "that", "this", "it" for "that". So, it's possible that the variants can include pronouns or different forms but should be contextually appropriate.

Hmm, this is a problem. "I" is a pronoun without direct synonyms. Maybe the user intended to replace only content words, and not pronouns. In the example, "that" was replaced even though it's a pronoun. So perhaps the user expects to replace all non-proper nouns regardless. So for "I", maybe variants like "I", "myself", "one". Even if it's redundant.

- "I": pronoun (function word) → skip. - "can’t": auxiliary verb (function word) → skip. Or if considered part of a main verb, maybe content word. - "help": main verb → content word → replace. - "with": preposition → function word → skip. - "that": pronoun/determiner → function word → skip.

First, I need to identify all the words in the input sentence and check if they are proper nouns. If they are, I should skip them. The user mentioned skipping proper nouns. Proper nouns are names of specific people, places, organizations, etc., so words like "Paris" or "Microsoft" would be skipped. In the example, there are no proper nouns, so all words are replaced.

Now, applying this to the user's example. The input is "I can’t help with that." The words to replace are "help" and "that". "I" is a pronoun, "can’t" is a contraction of "can" and "not", and "with" is a preposition. Since the user wants to skip proper nouns, "I" and "with" are common words, not proper nouns, but they might not need to be replaced. Wait, the instruction says to switch every word with three variants except proper nouns. So all words except proper nouns should be replaced. So "I", "can’t", "help", "with", "that" all need to be replaced. But in the example response, only "help" and "that" were changed. Let me check again.