How many verb endings to express "do this (please)"?

Question

I'm familiar with the て and てください forms of a verb to give a command/request and request, respectively. However, I've run across these other forms and really don't know which to use in what situation. I'll just list all the ones I've run across.

• 止めて下さい 　　　
• 止めてくれ
• 止めて 　　　
• 止めなさい
• 止めとけ
• 止めろ

I believe the first is the most polite and last is the most rude. The others in the middle are a guess. However, when and where to use these forms are a mystery to me.

Note: I'm focused on the endings not the verb itself. Also, if I've missed any, please feel free to add to my list.

Answer 1

• ～てください comes from the appending the verb くださる in imperative form. But because くださる is considered a polite verb (meaning "give to me"), its imperative is not felt as a direct command but a request. It is used when the speaker feels socially lower than the listener. (Asking for someone to do something for you especially if it's not expected of him places you "in debt" to the person, making you feel lower with respect to him)

• ～てくれ comes from appending the auxiliary verb くれる in imperative. ～てくれる means "to do for me". ～てくれ would be a command to ask someone to do something for you. It is rather neutral and can be used among peers of relatively equal standing.

• ～て comes from elision of the auxiliary verb that commands. As with many cases of elision, it is informal. It can be used among peers of relatively equal standing and has feminine undertones.

• ～なさい comes from the imperative form of the verb なさる which means "to do". It can be used when the speaker feels socially higher than the listener. (And the conjugation is 止めなさい or Verb-masu + なさい)

• Contributed by Chocolate: ～とけ is a contracted form of ～ておけ (て+お→と). It sounds more colloquial. ～ておけ is the imperative of ～ておく which means to do and leave it as it is.

• ～ろ(or よ) is just ろ(or よ) appended to the plain imperative form (止め). It is not particularly polite. It is direct though. Used when the situation does not call for politeness or it's more important to be quick and direct than to be polite.

Answer 2

I have some opposing opinions from what Flaw said, so I'll just give it here as a separate answer and let the voters decide if it's justified. There's hopefully some truth in both answers.

First, it is my understanding that ～ろ is simply not used unless you essentially want to bark at someone.

～なさい would be used not when you're "socially higher", but when you want to put yourself higher than the listener because you think you know better. Thus it would be quite impolite to use when talking to other adults, but it's common for commanding children.

～て is informal as Flaw says, and ～てください essentially becomes "please do ..". Hence the first is ok among friends or when you're talking to someone socially lower than you, and the second is more appropriate when talking to strangers or aquaintances (note that they don't have to be socially higher than you, but if they are, the second is more appropriate).

I'm not sure about ～てくれ more than that it comes from くれる as Flaw points out. Here I'd just like to say that requests are often better made in the form of a question. (would you (please) do .. (for me)?) One way to do so would be ~てくれませんか, although this one is best used among somewhat socially equal parts. If you're talking to your boss or some such, it would be more appropriate to use ~ていただけませんか. I'm sure there's even more polite ways to make requests, but none that I am aware of at this point. And if you want to ask a close friend to do something for you, something like ~てくれない？ may be the way to go.

I hope I gave accurate descriptions, I think it's really difficult to think about these things as "this one is used in this situation". It's probably better to understand the "feel" of the different words/phrases (there's a word for that, I'll edit as soon as I find it.. connotation?) and go from there. Then of course the one thing holds true no matter how you form your request/command is that informal speach patterns is best used among friends or socially lower aquaintances. For example, a waiter may be socially lower than you, but it's probably still appropriate to ask for help with the cooking at the table using ~てくれませんか.