Translation:It is not necessary for you to put your hand out.
Everything GermanLehrer has said is true, but let me add one cogent point:
It is a myth that one should not end a sentence with a preposition.
GScottOliver: tsk,tsk -- "out" here is not a preposition, it's a verbal complement. The prepositional phrase would be "out your hand" which makes no sense-- "out" as I said is a verbal complement and as such it can be placed alongside the verb: "It's not necessary to PUT OUT your hand" or at the end as DL has it: "It's not necessary to PUT your hand OUT." In other words it's not restricted to a pre-position as it would be (or should be) if it were truly functioning as a preposition. Here's another pair of sentences to illustrate what's happening. "I climbed up the ladder" & "I picked up my son". On the surface they look as though they're behaving the same way structurally: 2 prepositional phrases at work. But if that were the case you'd expect the same thing to happen if you re-arranged elements: "I climbed the ladder up" & "I picked my son up." In the first sentence you can't place "up" at the end because it's functioning as a preposition and must remain fixed for the prepositional phrase to make sense. In the second sentence 'up' is not functioning as a preposition, therefore it doesn't have to remain in that pre-position and can be placed at the end without a change in meaning, precisely because it's not functioning as a preposition but rather as a verbal complement.
GScottOliver: Here's another pair to illustrate what I said below: "The runners ran up the hill" & "The runners ran up the score." If you were to re-arrange "up" you'd get: "The runners ran the hill up" & "The runners ran the score up." Obviously only the second makes sense and that's because in the first sentence "up" is functioning as a true preposition, indicating direction "up the hill" and is fixed in its position. In the second sentence it's not acting as a preposition at all, but as a verb complement; thought of another way, the verbs in the two sentences are "ran" in the first sentence, where? "up the hill" (prepositional phrase), whereas in the second the verb is "ran up", what? "the score." (verb + complement).
I've never come across this phrase as an idiom. But it makes perfect sense to me literally in relation to bus transport. There used to be in the UK (possibly still is in London) a distinction between compulsory bus stops and request stops. At the former the bus has to stop. At the latter it only stops if someone puts their hand out.
So if you put your hand out at a compulsory stop the driver or conductor might well say "There is no need for you to put your hand out."
Of course, the same distinction may not apply in Italy!
If that's true, why on earth would we be learning a British idiom in Italian? It would be nonsensical in Italian, then? As for the English grammar, it's perfectly acceptable to end a sentence with a preposition. It was some monk who tried to prescribe that one shouldn't, but he was importing a rule from Latin that makes no sense for Germanic languages, including English.
Please remember at all times--English is not one language. In informal English, you're right that a preposition can end a sentence, but in formal English, it may not. Yes, we do use formal English in business and in school. Generally, if it is written, a preposition may not end a sentence. It matters little where the rule originated. It is still a rule. Note that I did not say "where the rule comes from," as I am writing to you. Normally, there's a non-pedantic way to avoid breaking the rule, but sometimes it requires creativity to comply. I might also note--I am an American, speaking American English, The idiom is not exclusively British.
English idiom would be to "to hold your hand out" which means to ask for charity. DL doesn't accept this as a translation however.
The only time I ever got asked "to put my hand out" was to receive a punishment, by being hit with a ruler, by the teacher. Since people don't normally ask for punishment, the sentence sound very unnatural in english. DLs use of subjunctive present english translations, is punishment enough to native english speakers. I hope Italian learners doing the reverse tree don't get the idea that it OK to speak like this in English...
I am English and have heard the phrase "you don't need to put your hand out" many times. In English it means you don't need to get involved to help with someone else's problem. For example, a conversation might go like this: "My brother is in real trouble!" "Well, you don't need to put your hand out." Whether the same idea works in Italin, I don't know.
Congratulations. Of the many comments here I think your explanation of the English meaning is the best. Now would some native Italian please confirm whether the Italian has the same idiomatic meaning of not needing to help? Or is it just a literal translation? I am constantly looking for interesting expressions and their equivalents so does Italian have its own idiomatic way of saying this?
See this link for phrases that call for the subjunctive tense in dependent clauses. One of them is 'È necessario che...' They list 11 others. http://italian.about.com/od/verbs/a/italian-verbs-present-subjunctive-tense.htm
Metta is congiuntivo presente, metti is indicativo presente. Indicativo is for stating facts, congiuntivo is used to be polite, to express opinions, to describe things that may-have-or-may-not-have-happened-that's-not-the-point, among other things. So, in this sentence, congiuntivo is used because the speaker is not stating the other person really, in fact, did something (put out a hand).
Also see the link I posted above. Some expressions are always followed by verbs in congiuntivo mood, é necessario is one of them.
DaveVelo1: I think DL's translation is fine, as is yours. I think both of them sound natural and are grammatically correct. As for your question, in Italian (as in German e.g.) the possessive adjectives are commonly omitted with parts of the body (and articles of clothing) unless the context is unclear. In this example, think of it as: who else's hand would someone be told it's unnecessary to put out?
I wont guess why begging comes to your mind when you read ".. stick out your hand", but I am afraid for you it has some kind of negative connotation.
It's not about finding better words for "stick" but better words for "put". When I tried "stick" instead of put this was in my mind https://www.youtube.com/watch?v=aIAu7KPWco4 - so, hello again ;) .
In the context with begging the better phrase might be "put the tin can out" (more idiomatic) or "hold the hand out" (more natural).
About hyper-correction: Each of us molds language. That can be actively or passively (just by ignorance). We can leave it to extremists, to companies like Google, to propaganda, to dogmatic religions to shape the language for us in their interests, or we can protect our language and handle it with care for it's the basic tool we have to think, to communicate, to understand others and to express ourselves, to negotiate peace instead of letting money or weapons "talk" (say bribe, fight and kill). Yes, you might be right being afraid that I "hyper-correct", at least that it might happen sometimes while trying to find my way through foreign languages like English, Italian. It's a bit trial and error, "vallen en opstaan" Dutch for "to fall and stay up again" I probably run too fast too often, but I think that's not the worst thing one can do in a learning environment.
I don't know if you are pretty new to DL or if you just made a new account, but participating in the forum, is a great way to get to know the quirks and the possibilities of a language. Thank you for your response!