"With the purpose of" vs. "With the intention of"

Solution 1:

Pronunciation isn't my strongest point _ __ _ I've decided to improve it. I've borrowed some Spanish DVDs from the library, with the _ __ _ of listening to native speakers and trying to copy them.

The first gap (in my version) would require so or ,so or ;therefore . Given the comma, 'therefore' is ungrammatical as it never follows a comma.

The second gap could certainly be filled by intention. 'I've borrowed some Spanish DVDs from the library, with the intention of listening to native speakers and trying to copy them.' is a paraphrase of the more colloquial 'I've borrowed some Spanish DVDs from the library. I thought I'd listen to some native speakers and try to copy them.'

It could also be filled by purpose. However, construction-wise, 'for the purpose of' is more idiomatic than 'with the purpose of'. And semantically (and this is probably why the preferred choice of preposition is as it is), there is more of a flavour of the ultimate achievement than need be present with 'with the intention of' and certainly 'I thought I'd'. This doesn't sit too well just before 'listening to'. 'For the purpose of' would sit better with 'really getting to grips with idiomatic Spanish' (Aim, less 'ultimate achievement'-flavoured would sit happily with both 'listening' (ie the strategy employed) and proficiency (ie 'copying' – speaking like – 'the native speakers': the ultimate achievement)).

Solution 2:

Considering that "the learner has to supply the one word answer that best fits," the obvious answer would be
intention

because that's what goes with the given preposition with.

If the preposition provided had been for, the choice would be purpose.

The purpose/ intention of the question appears to be to test the knowledge of collocation of the prepositions.