yes, you are right, if you get the French sentence first, you can imagine that it is about something rather than someone, or even an animal.
Verb être, like all other verbs in French, has a different form according to the subject:
je suis, tu es, il/elle/on est, nous sommes, vous êtes, ils/elles sont
Is there a difference in pronunciations of 'il' and 'ils'? I thought this sentence said "Ils est forts."
The clue here is in the verb. Il est fort (He is strong) v. Ils sont forts (They are strong) Otherwise, the difference is that when next to a vowel, the 's' in Ils is carried over in a liaison.
no, is not a differnet prononciation of "il" and "ils", but for "ils", the verb will be "sont" and for "il" it will be "est" (I am french, sorry if my english is not correct...)