Question

If a language does not use determiners/articles, context or other words will tell you whether a noun is singular or plural.

Answer 1

Yes.

Step-by-step explanation:

Consider the simple method for English in which affixes denote singular or plural status for nouns.

For example, -s and -es indicate plural, and in the absence of those affixes, the noun is singular.

Of course, there are exceptions, such as fish, deer, and sheep, to name just a few.

In those cases -- if you are truly excluding any (presumably verbal) context as you stated, then you could indicate quantity by using fingers.