a platform or platform

[norwolf]

We say:
Polar bears live mostly on sea ice, which they use as a platform for hunting seals.
To my ear, we also say:
Polar bears live mostly on sea ice, which they use as platform for hunting seals.
Right? Please.

[norwolf]

Whereas the indefinite article is required in the previous examples, there is

vacillation in the following cases (cf 'unique role', 5.42):

her duties as (a) hostess

my appointment as (a) lecturer

Jung as (a) thinker
A Comprehensive Grammar of the English Language
Why does the writer say there is vacillation in the cases with the complements?
Is there anything different between the previous one and them?
Is the reason that they refer to persons?

[azcl]

***Not a teacher***

If you drop the indefinite article, it suggests that the person is the only one of this category (unique - as mentioned in your post), or at least you are drawing attention to their uniqueness.

Barak Obama might say "As President, I speak to you today..." as it is his unique role. I would say the same of:

her duties as (a) hostess

....as at a party, she would presumably be the only hostess, so missing the article is fine and draws attention to her uniqueness as hostess - whereas 'as a hostess' does not.

Similarly,

my appointment as (a) lecturer

without the article suggests you are the only lecturer.

Jung as (a) thinker

Doesn't sound right to me without the article.

When was your grammar book published?

Ade

[norwolf]

A Comprehensive Grammar of the EnglishLanguage,Longman,1985
by R·Quirk