Translation:Give me half.
It should count, but technically "下さい" is a polite way of saying "give me." Because it's polite speech, the "please" is implied, but this sentence is literally "give me half," but it doesn't sound rude in Japanese. I'm not positive it's covered in Duolingo, but there are something like five or six verbs that mean "to give," and they all convey the social status of both the giver and receiver. There's different verbs for "my boss gave me" and "i gave my boss," for example. That's probably why Duolingo isn't taking "please," here.
When all else fails, I've found, just go with straightforward, literal translations. I just translated this as "Half, please" and it was accepted. I generally prefer to go with the most literal translations because I find it more helpful for understanding the core mechanics of the language. More natural-sounding English translations can always come later.
At least for "Can you give me..." I can understand why it wouldn't accept it. Yes, in English, "Can you give me x" is requesting something, but it's phrased as a question rather than as an imperative sentence. "Half, please" is a request, but not a question. This is the difference between literal and colloquial translation. "Can you give me half, please?" more literally translates into asking about the other person's willingness/ability to give half. "Half, please." is making a demand with no inquiry attached.
Young people often say 'can I get' and no please nowadays which I sadly have to live with, but I think more traditional answers that a lot of people still use should be accepted too. For example 'half please' or 'may I have half please' as I assume the intention is to ensure the person understands the Japanese not to enforce a certain style of english
Surely the whole point is to check here first with respect, with more knowledgeable individuals in case of mistake. Only then go back to flag it if you feel the same. So discussion/complaints, this is first port of call. If everyone just flagged all they disagreed with it would flood Duo with a whole lot of personal mistakes. Ive found this myself where checking here first, I discover a new context which makes sense of something I was convinced was wrong. Regards.
Japanese is a very contextual language. The problem is that duolingo doesn't supply us with the necessary context. They are also not good at teaching grammar so I use it only for revision and vocabulary. Used as a primary source for learning Japanese it would be horrible.
is the other way around, the kanji for "part" is used in the word minute. 十分【じゅうぶん】for example means "enough; sufficient; plenty; adequate; satisfactory". That one takes the kanji for 十 "whole" and 分 "part". But 十 is also used for ten, because of the idea of 10 as a full set.
That is american english. British english is May I have or can I have. If we use 'can I get' in say a cafe it would mean either you are asking if you can go and get the item yoyrself or it can just as likely be taken as a sarcasm implying you've been waiting too long for service.