I put "The juice is sour like lemon" - but it was wrong. So how would you say what I wrote in Hebrew? Or are they both accepted?
Either your answer should be accepted, or otherwise it's because your english sentence may not be grammatically perfect- maybe they want you to say "the juice is as sour AS a lemon"....
To English knowers: Why is lemon put as a lemon here? Is this the way you would say it? Would not the juice tast sour as lemon in general, not as A lemon (one piece of lemon)? Or is this the right way in English?
Similes in English take a standard form of " as xxx as yyy" (so although "like" is a perfectly good word it doesn't sit comfortably in the pattern).
Thinking about your question: as a native speaker of English, I would normally use the definite article here. So "As sour as a lemon" (or "as lemons"... but the Hebrew isn't plural in this sentence)
I have to admit I'm not sure WHY just saying "lemon" as a sort of abstract flavour doesn't sound right, but it doesn't. Perhaps because similes are often using something that's "concrete" to describe something that's not?