What's the difference between ～てください and ～ていてください?


This question has come up on the side of at least a couple of other questions,
but I don't think it's been definitively answered, so let's see if we can come
up with something solid.

After going through the first ten pages of Google results for both "ていてください"
and "ていて下さい" (very scientific, I know), I found 43 verbs and expressions that
precede these forms. The most common:

[code]

    待つ (まつ):                50 results
    見る (みる):                33
    楽しみにする (たのしみにする):  25
    覚える or 憶える (おぼえる):  19
    生きる (いきる):              9
    期待する (きたいする):         5
    見守る (みまもる):            4
    強いる (しいる):              3
    離れる (はなれる):            3
    知る (しる):                 3
    思う (おもう):                3
    
[/code]

待つ is somewhat expected, but there are some interesting entries here, such as
生きる and 離れる. How is 生きてください different from 生きていてください, and likewise, how is
離れてください different from 離れていてください? At a minimum, let's try to answer:

  1. **What is the difference in nuance between these two?**
  2. **When should you choose one over the other?**

Bonus points if you can draw from a trusted reference.

Related:

  * [What does the final て in 待ってて signify?](https://japanese.stackexchange.com/questions/948)
  * [deceze's answer for Am I coming or going? 戻ってくる vs 戻っていく](https://japanese.stackexchange.com/questions/1204/am-i-coming-or-going-vs/1208#1208)




I think each verb is somewhat a case of its own, but generally speaking they
all seem to relate somehow to the progressive nature of the ～ている form.

If we get to the specifics, here are my impressions, based on my experience,
intuition and grammatical understanding (all of them seem to point to the same
thing in this case, which is good). Sorry, no references now, but maybe I'll
try to search for some academic papers later. There's a good chance you can
find some on Google Scholar:

  * **生きていてください**  
I'm almost positive I've already heard or seen it somewhere. It seems to mean
something along the lines of "Please keep being alive" or "Please stay alive",
instead of `生きてください` which means just "Please live", with an implied meaning
such as "living through something" or "choosing life over death", but not
"staying alive". According to Google, it's actually much more common than
`生きてください`, and that's only natural, since in English too you'd usually ask
people to stay alive instead of just "live". :)

  * **離れていてください**  
This is again the case of a request for keeping some state for a prolonged
period instead of just doing a single action. I don't think I've encountered
this specific verb in this form (though it does seem very common according to
Google), but it's easy to understand it as "separate and remain separated", or
maybe even more simply "stay away", "keep distance".

  * **覚えていてください**  
_Remember for a prolonged period_. Or as we'd probably say in English: _keep
in mind_.

  * **見守っていてください**  
_Observe closely for a prolonged period_. Or idiomatically: _Keep an eye_.

  * **期待していてください** _Expect for a prolonged period_. Or idiomatically: _stay tuned_.

You've probably noticed how much I've had to resort to idioms in English to
translate these Japanese phrases more accurately. That's because English
doesn't have an progressive imperative construction. And you may have also
noticed I heavily used the verbs _keep_ and _stay_ in most of the idioms I
gave. That's because while English cannot express a progressive imperative, it
can always express a meaning of remaining in a certain state by using verbs
such as _stay_ , _remain_ and _keep_. These verbs usually take an adjective or
an adverb (including a preposition-as-adverb) and not another verb, so their
use is very idiomatic and not as regular as in Japanese.




I think each verb is somewhat a case of its own, but generally speaking they
all seem to relate somehow to the progressive nature of the ～ている form.

If we get to the specifics, here are my impressions, based on my experience,
intuition and grammatical understanding (all of them seem to point to the same
thing in this case, which is good). Sorry, no references now, but maybe I'll
try to search for some academic papers later. There's a good chance you can
find some on Google Scholar:

  * **生きていてください**  
I'm almost positive I've already heard or seen it somewhere. It seems to mean
something along the lines of "Please keep being alive" or "Please stay alive",
instead of `生きてください` which means just "Please live", with an implied meaning
such as "living through something" or "choosing life over death", but not
"staying alive". According to Google, it's actually much more common than
`生きてください`, and that's only natural, since in English too you'd usually ask
people to stay alive instead of just "live". :)

  * **離れていてください**  
This is again the case of a request for keeping some state for a prolonged
period instead of just doing a single action. I don't think I've encountered
this specific verb in this form (though it does seem very common according to
Google), but it's easy to understand it as "separate and remain separated", or
maybe even more simply "stay away", "keep distance".

  * **覚えていてください**  
_Remember for a prolonged period_. Or as we'd probably say in English: _keep
in mind_.

  * **見守っていてください**  
_Observe closely for a prolonged period_. Or idiomatically: _Keep an eye_.

  * **期待していてください** _Expect for a prolonged period_. Or idiomatically: _stay tuned_.

You've probably noticed how much I've had to resort to idioms in English to
translate these Japanese phrases more accurately. That's because English
doesn't have an progressive imperative construction. And you may have also
noticed I heavily used the verbs _keep_ and _stay_ in most of the idioms I
gave. That's because while English cannot express a progressive imperative, it
can always express a meaning of remaining in a certain state by using verbs
such as _stay_ , _remain_ and _keep_. These verbs usually take an adjective or
an adverb (including a preposition-as-adverb) and not another verb, so their
use is very idiomatic and not as regular as in Japanese.

