point duty vs Britain

point duty and Britain both are nouns.

Word	Noun	Adjective	Verb	Adverb
point duty	Yes	No	No	No
Britain	Yes	No	No	No

point duty (noun)	Britain (noun)
the control of traffic by a policeman stationed at an intersection	a monarchy in northwestern Europe occupying most of the British Isles; divided into England and Scotland and Wales and Northern Ireland; `Great Britain' is often used loosely to refer to the United Kingdom