<Ask not><not ask> what your country can do for you

[WilliamTaft]

Source: VOA Learning English - America's Presidents - John Kennedy: Young

Supporters of the new president loved his energy and sense of hope. In his most famous line, Kennedy said, "Ask not what your country can do for you - ask what you can do for your country."

What's the difference if I say "not ask" in this context?

 

[5jj]

Not ask is not possible. It could be Do not ask or Don't ask.

 

[Skrej]

Perhaps if you view it as an imperative, that will help. Also, try substituting something else for that 'what' clause:

Ask not the color, but ask the size. (Ask about the size, not the color).

The construction is purposely a bit unnatural to emphasize the oratory effect of the line. Although Kennedy's words are very effective in that regard, it's not a good example of natural speech. It wasn't meant to sound natural or common - it was a motivational speech to an entire nation, meant to inspire hope and a sense of possibility. It was a challenge to accomplish great things.

Also notice the intentional repetition of the 'ask not' phrase. The original could have been stated thusly:

Ask not what your country can do for you, but rather what you can do for it.
(Ask not the color, but rather the size.)

However, it's a more effective oratory device to repeat 'ask not', partially because it sets up a contrast between the repetition of 'ask not', and the contrasting rearrangement of 'you' and 'your country'.

So, while it's a great speech, it's probably not a good example to pick apart for language learning. It's certainly nothing you'd want to model, unless perhaps you end up needing to deliver a motivational speech in English.