What does the phrase in red mean and why is "an" used instead of "the"?
"In an agony of frustration, I heard Susan moan that she had dropped her watch..."
Thanks in advance!
This is prepositional phrase which means a state of metal suffering/disturbance due to frustration(disappointment/failure to achieve the desired result). Since "agony" is an uncountable noun use of 'an' is OK. But why the indefinite article instead of definite article "the"? This is a tricky question. I think because "agony" has no previous or specific refernce, use of indefinite article is perhaps justified.