"Give me a plate, please."
Translation:Дайте тарелку, пожалуйста.
I believe that тарелка is always nominative singular. Here, we need to use the accusative because the "plate" is the direct object of the verb "give." https://en.wiktionary.org/wiki/тарелка#Declension
Perhaps you mean to ask if it would be appropriate to use the genitive case here (тарелки) to indicate "some plate" or "any plate." I am not a native Russian speaker, but this doesn't sound right to me -- I think of that case usage as generally limited to non-countable nouns (e.g. "some water" --> воды). It would be great if a native speaker could weigh in, though.
дайте (мне)1 тарелку, (а)2 не яблоко.
1: "me" is not necessarily needed.
2: I am not sure, but I think the 'а' is not necessary, either. I don't know how to explain its meaning in English, but I can try with a few examples. It can be approximated to "and" but it's not the same (you can't say "x and y" with it)
Я женщина, а не тарелка. - I'm a woman, (and) not a plate
Рисую, а не танцую. - I'm drawing, not dancing.
As you see, it's some sort of a negating meaning. But it can also be used like this:
Я женщина, а ты — мужчина. - I'm a woman, and you (are) a man.
So it's a sort of "this is x, while this is y (and thus not x)" meaning. I'm not a native speaker of either Russian or English, but I hope I brought the meaning closer to you! :D I strongly advise reading the lesson tips, too (which I haven't, hahaha). Better explanations could be found there. Good luck with your language learning!
The difference is the aspect, which, unfortunately, may take some time to explain. Дать is perfective; it is for single specific actions. Давать is imperfective, used for habitual, repeated, ongoing actions or as the name of the action in general (also, only imperfective verbs have a present form).
Slavic verbal aspect is difficult, so I will skip the 200-page-long explanation/theory for now :). Linguists publish papers and heavy books on this subject.
For imperatives, we obviously use the imperfective for repeated actions or when you focus on the process ("Говорите, пожалуйста, быстрее"~ "Speak faster, please").
But we ALSO use imperfective verbs for simple commands sometimes. It happens when the listener should do the action immediately, you focus on the starting point, and cooperation is expected because of the situation (e.g., the listener is waiting for your signal to pass you the plate).
In this sentence, either could fit without пожалуйста; with "please", appealing to the action being "obvious" or "expected" sounds odd.
Дать and давать also have other uses. Дать is used to command someone let someone do something ("Я не дал ему закончить"="I did not let him finish"). Давать is used in "let's do something" sentences—again, the use depends on the aspect (e.g., "Давайте играть"/"Давайте поиграем"="Let's play").
Thanks a lot for this elaborate explanation! Luckily, my native language is also a Slavic one - сербский - so while I didn't remember to compare immediately, I can easily compare now and we can skip 200 pages for good :D
Aspect, imperatives and commands, other uses - I understood all that; the following bit is only a little confusing:
'In this sentence, either could fit without пожалуйста; with "please", appealing to the action being "obvious" or "expected" sounds odd.'
Yes, you are correct that the plate (the accusative) is the direct object of the verb. This sentence follows the same pattern as an English sentence as far as cases. For simplicity of the demo below, I'm going to leave off the "please."
English: Give me a plate.
Subject/Nominative: [You (implied in an imperative sentence)]
Indirect Object/Dative: me
Direct Object/Accusative: plate
Russian: Дайте мне тарелку.
Subject/Nominative: [Вы (implied in an imperative sentence)]
Indirect Object/Dative: мне
Direct Object/Accusative: тарелку
Note that we can rearrange the English phrase, "Give me a plate," where the indirect object is me, to, "Give a plate to me." At that point, there is technically no longer an indirect object, and me has become the object of the preposition. But that is just a little nerd-fact that I remembered after reading my English grammar handbook from junior high. I love that book.
We always apply it. It is just that consonant-ending masculine nouns have their Accusative the same as Nominative IF they mean objects. The rule also applies to plural forms of all nouns.
Nouns like мама, тарелка, девочка, Россия, Вера, Анна, Клара, тётя, бабушка, кошка have a separate Accusative in the singular, ending in у (or ю) regardless of what the word means.
Feminine nouns like ночь, мышь, лошадь have their singular Accusative identical to their Nominative regardless of the meaning.
So, in this case тарелка is feminine, so it gets "у" ending regardless of whether animate or inanimate.
From Wikibooks article on Accusative:
Masculine - (Inanimate) As nom. (Animate) +a, -я As gen.
Feminine - (All) у, ю, ь
Neuter - (All) о, е As nom.
Plural - (Inanimate) ы, и, etc As nom. (Animate) ов, ев, etc As gen.
Just the ты/вы distinction. It is always -те at the end for the plural you (though, the reflexive -сь will stay at the end if present): дай/дайте, читай/читайте, скажи/скажите, говори/говорите, садись/садитесь, спи/спите, живи/живите, иди/идите, будь/будьте, радуйся/радуйтесь.
Nouns like мама, тарелка, девочка, кошка, пицца, папа, мужчина, земля, Мария, Виктория, Никита, Саша have the -у/-ю ending in the Accusative regardless of animacy (in the singular).
The animacy matters for consonant-ending masculine nouns in the singular and ALL nouns in the plural.