What is the reason for "естб" in this sentence? Would the sentence work without it?
Not quite, it would be more like stating that your sisters are right now at your place.
"есть" is a form of the "to be"-verb, stating existence. That's how you describe possession in Russian to give new information.
However, есть is dropped when you rather describe properties or quantities (I have a clever sister/I have many sisters). Which makes it a bit different from English "have", which works in both cases,
I have seen «сестры» in other sites, and not «сёстры». Could it be that both are correct?
using Ё is optional. Since our course is aimed at beginners, we are very consistent in always spelling words with "ё" precisely, even if a native speaker would not confuse it with anything else
I've read that ё is pronouced /yo/ so I thought сестра and сёстра were two different things since i believed the other was pronounced /syostra/. Am I supposed to read other words with ё the same way I should pronounce е in сестра?
Yes, sure. This is what makes Russian hard for a beginner who wishes to speak without any trouble whatsoever. There is a limited number of frequent patterns, however.
Here is the whole paradigm, ordered as Nominative, Accusative, Genitive, Prepositional, Dative, Instrumental:
- singular (NAGPDI): сестра́, сестру́, сестры́, сестре́, сестре́, сестро́й
- plural (NAGPDI): сёстры, сестёр, сестёр, сёстрах, сёстрам, сёстрами
Whoa, crazy. Now I have one more question. From what you said earlier, "using Ё is optional." Is that only in the plural? Is the singular supposed to be strictly "е?" Or is the singular supposed to be сёстра?
"Using Ё is optional" is strictly about spelling. It is like no one forces you to write naïve and café. It does not affect pronunciation.
I use Ё consistently, though.
Well, сестры can mean у меня нет сестры - I have no sister. Сёстры - sisters.
I can't get use to the pronounciations here. the ы at the and confuses me, sounds like "e" and despite that i knot it can't be сёстрe in this sentence, i still write that :(