[Grammar] Be to infinitive - was to bring

[Lumia625]

Hello there,

I saw a new structure in a text which seems somehow odd for me. After searching a lot finally I found out that this structure called "Be to infinitive". I saw some explanations and examples about this structure and learnt some new things about it, but I cannot find an explanation which is related to my text.

Can you teacher guide me how I should translate "was to bring" and help me which sub category of "Be to infinitive" is related to my question ?

Here this is the whole text :

The crucial additional step was to bring another specific noise (e.g.gOOd) into sombination with the first to build a complext message (bEEr gOOd).

Thank you so much,

 

[Raymott]

I guess your understanding of the "be to infinitive" is similar to on this site:
http://grammar-teacher.com/understanding-english-grammar-to-be-infinitive/

Your example is different. "The crucial additional step was to bring another specific noise ..." This means, "To bring another specific noise ... was the crucial next step." or "Bringing another specific noise was the crucial additional step. " You can't do either with any structure discussed on that page. Eg. "The peace talks were to end in failure" can't be rewritten as, "To end in failure were the peace talks." or "Ending in failure were the peace talks."
"He was to be here at midday" means "He was supposed/meant to be here at midday." Is that your understanding of the "be to infinitive"?
Your example can't be written as "The crucial additional step was supposed to/ meant to bring another specific noise."

 

[Lumia625]

Is that your understanding of the "be to infinitive"?

Yes, its is. By your explanation I could understand it completely.

Thank you indeed,