Translation of 'Elle portait un manteau cher . . "

Question

Why is this not translated as "she was wearing . . ." which would be consistent with the description of imparfait from the specific grammar lessons on Imperfect being equivalent to English use of 'was . . ' or 'was ..ing'.  It seems to me that 'she wore . . ' would be more consistent with passé compose (Elle a porté . . .)?  Noting further that for 'I bought . . . ' the origin of the translation was passé composé - 'J'ai acheté ...' in the same set of examples above.

Accepted Answer

Unfortunately, the correspondence of English and French is often misleading when it comes to the use of imparfait. Don't get hung up on the English tense. Try to get a sense of what one tries to express.
She wore a coat when she went out. -- Elle portait un manteau quand elle est sortie.
In this example you can use perfect tense in English but you'd use imparfait in French for the first part because it describes a kind of state (she wears the coat for a period of time, it's not an event).
It gets even more obvious when in this sentence:
I loved chocolate. -- J'aimais le chocolat.I was at school today. -- J'étais à l'école aujourd'hui.
There are so-called verbs of state, which describe a state of being rather than a specific action (as, e.g., aimer or être). They will usually ask for the imparfait.