most interesting or the most interesting

Question

a. Most interesting was what we saw on the fifth day of our stay in Paris.

b. What was most interesting was what we saw on the fifth day of our stay in Paris.

c. What we saw on the fifth day of our stay in Paris was most interesting.

In which case:

1. 'Most' means 'extremely

and in which case:

2. We have a real superlative

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Can one say

a. The most interesting was what we saw on the fifth day of our stay in Paris.

b. What was the most interesting was what we saw on the fifth day of our stay in Paris.

c. What we saw on the fifth day of our stay in Paris was the most interesting.

?

Many thanks.

Answer 1

My vote is for, 'The most interesting (thing/of all) was what we saw on the fifth day of our stay in Paris' The most interesting of all was what we saw on the fifth day of our stay in --Paris This sounds good. But, you need to say what was it in the following sentence. The sentence has a feel that some thing is yet to be revealed.

Answer 2

Most interesting was what we saw on the fifth day of our stay in Paris.

To be is a copular verb that can link adjectives/adjective phrases to nouns/noun phrases. So interesting is an adjective and doesn't need an article. Doing this requires context so the listener/reader knows the type of thing that would be interesting.

When you try:

The most interesting was what we saw on the fifth day of our stay in Paris.

Here you are "noun-ifying" an adjective. You could only really get away with this if you say directly what the interesting thing was. Doing this also really requires previous context so that the question "the most interesting [what?]" is answerable without a lot of thought.

I was looking at vehicles. The most interesting was the vintage blue car.