I am not clear on why both the spelling "אינו" and "איננו" are acceptable as part of the answer here-- can someone explain it to me?
the words אינו and איננו have exactly the same meaning and you can always replace one with the other. Why does Hebrew have both? Historical reasons. :)
Is אינו the same as לא in all cases? (Missed this sentence because of a multiple-choice that had this as the only correct answer…)
I thought ain was the opposite of yesh, the present tense, and lo was used in the past or future. Maybe that is biblical hebrew or just my error.
Can you do: הוא לא מחמם את זה כי הוא כבר חם ?
Note: uses הוא for זה in the second half.
I think, in that case, you'd need both clauses to match - הוא לא מלמם אותו, כי הוא כבר חם.
hu lo mechamém et ze, ki ze kvar cham.
I am confused too, i thought איננו meant gone?
Yes, that is also a possible translation, alongside a negation, like here.
Whats the difference between כבר and עדיין
It's not really easy to answer that question in one post, but in general:
כבר - already
עדיין - yet, still