"for improving" vs "to improve"

[shannico]

Maybe this could help to make my explanation clearer.
Learning English | BBC World Service

[5jj]

Your explanation was clear enough. I simply said that I feel we don't necessarily make that distinction.

The link you provided appears to agree.

[shannico]

Agree with what you maintain or with my explanation?
By saying that you don't feel a native speaker would make that distinction, you might encourage the idea that the two are absolutely interchangeable.
Genuinely I think it's good for a learner to know that for+ing may occur when talking about the function of an object and the same doesn't occur when talking about an action driven by an agenda.

[5jj]

Agree with what you maintain or with my explanation?
With what I said.
By saying that you don't feel a native speaker would make that distinction, you might encourage the idea that the two are absolutely interchangeable.
I said that they we don't necessarily make that distinction.
Genuinely I think it's good for a learner to know that for+ing may occur when talking about the function of an object and the same doesn't occur when talking about an action driven by an agenda.

Fine, but originally you did not use the word 'may'.

[shannico]

Fair enough. I mightn't have used may because I was focussing on why the two constructs are different rather than on why they may be interchangeable.

[hoangkha]

[not a teacher]
According to PEU by Micheal Swan
Infinitive clauses of purpose
We often use an infinitive to talk about a person's purpose- why he/she does someting.
- He went abroad to forget.
- I am going to Austria to learn German.

The purposes of things :-ing forms and infinitive.
For can be used before the -ing form of a verb to express the purpose of a thing- what it is used for.
-An altimeter is used for measuring height above sea level.
When the clause has a person as subject, it is more common to use an infinitive to express the purpose of a thing.
- We use altimeters to measure height above sea level.

[5jj]

Swan's ideas are useful, but note the words'often', 'can' and 'more common'.

Like the ideas in the link provided by shannico, they give good guidance. I just do not want learners to go away with the idea that they are 'absolute rules'.

[Mannkavi]

Typing the same question three times in a row isn't going to make us answer any faster. The opposite, in fact.

@emsr2d2
Sorry for the inconvenience. But I didn't mean that. In first question I just asked the first thing that came in my mind after reading the replies. Then I thought to make my question more clear so i posted second question. After some time I realised I should ask the question in general form as you said, "I know, I need to work hard for improving my English" is incorrect, so I posted it in general form.

[Mannkavi]

I don't feel that we necessarily make that distinction.

Ok. Is that mean we can use "to verb" in place of "for verb+ing" ?

[Mannkavi]

Maybe this could help to make my explanation clearer.
Learning English | BBC World Service

Now I understand the difference.
Thanks to you shannico.