
Originally Posted by
THE ADVANCED LEARNER'S DICTIONARY FO CURRENT ENGLISH WITH CHIESE TRANSLATION (1982) earnest. adj. serious; determined: an ~ worker ( pupil); an ~ Christian, one who conscientiously practise beliefs. n. in earnest, in a determined, not in a joking manner; seriousl(ly):If you work in ~, you will succeed. I'm perfectly in ~ , am not joking. It is raining in real ~, heavily, and likely to continue. ~ly adv. in an ~ manner: We ~ly hope that... ~ness.

Originally Posted by
Jiang No. 1: In the phrase 'in earnest' the word 'earnest' is a noun. But the phrase can be adj. as well as adv. Am I right?
No.2: What's the difference between 'earnest' when it used as a noun and the noun form 'earnestness' ?
With regards to the dictionary entry above,
in earnest is listed as a noun (
n.) and yet within
the examples provided, it functions as an adjective. What's that about?
Within the phrase prepositional phrase 'in earnest', 'earnest', a noun, means, solemn promise or pledge. To do something
in earnest (adv.)means, to do something
in which a solemn promise is madeto oneself and/or others.
As a noun,
earnest has the following dictionary entry (Encarta):
earnest. n. a small advanced payment that confirms a contract; a sign, foretaste, pledge of something to come. (French erres, Latin arres, Greek arraboun 'pledges')
The difference between 'earnest' and 'earnestness' is this, the former is a pledge and the latter is a characteristic:
earnestness. n. an earnest and sincere feeling. The trait of being serious.
EX: Her
earnestness is what makes her a great employee. (noun)
EX: The
earnest was 35%. (noun)
All the best,