How should I understand the grammatical property of "soit" in this sentence?

Question

J'ajoute que la Seine, qui longe mon jardin, est navigable jusqu'à Rouen, comme vous le savez sans doute. Je voyais passer chaque jour de grands navires soit à voile, soit à vapeur, venant de tous les coins du monde.

What is the grammatical property of "soit" in the sentence? When I looked it up into the dictionary, it is "être" in the present tense with subjunctive mood. It seems that one would never used "be" in English in this way. Would anyone explain the use of "soit" here?

Answer 1

In this context, you shouldn't just take the word soit by itself, but the expression soit... soit, that you can translate as either... or. So in this sentence, we want to say that the ships that he see everyday are either sailing ships or steamboats.

Let's take another example:

Je vais au marché soit le lundi, soit le mardi.

You can translate it as:

I go to the market either the Monday or the Tuesday.