it/that

[Soup]

Thanks Soup.

If I followed what you have said correctly, you believe that the structure, when used with "it", could be be interpreted different ways, in one of which "it" is an expletive and in the other a pronoun.

Yes, that's right; the problem is referencing. Consider,

• I thought I saw a cat, but it (/the cat that I thought I saw) wasn't a cat, it (/the cat that I thought I saw) was a gun.

In the example above, it refers to 'a cat', but below, 'it' lacks a reference:

[1] Are you kidding? It (/___ that I saw) was a gun on the table.
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It lacks a reference. Pronouns refer backwards, not forwards, which is why [1] is awkward and where the expletive reading comes in.
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I was watching a film recently in which I thought I heard this sentence: It was evidence we found in your trunk.

The sentence struck me as "off". I would have used "that". Actually, I was surprised when I heard the sentence. Hence my question.

It's a good sentence. It's called a cleft (See here):

Cleft: It BE + focus + clause

• It was evidence that we found in your trunk.
• It was in your trunk that we found evidence.

With cleft sentences, the focus is on the 1st constituent, the one after It was ('evidence' and 'in your trunk'). Here is your example 1:

• It was a gun that we saw on the table. :tick:

The focus is on 'a gun' and clefting works in the dialogue you provided as long as you add in the second part of the cleft, the clause ('that we saw'):

A: Why didn't you argue with him?
B: Are you kidding? It was a gun that we saw on the table. :tick:


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[navi tasan]

Thank you Soup.

I have to apologize. I made a mistake in my post. The sentence I heard was:

It was evidence in your trunk.

That was why it sounded strange to me. When I was writing my post, I just wrote a sentence that sounded much more natural to me. I wrote "It was evidence we found in your trunk."

Sorry about the mess-up.