Comparison of sentences

I am having a problem translating some of the sentences in the current
translation exercise (1.1.7).  I am able to translate the comparison
of one item with another as, for example:

I am heavier than he.
m-us n-úsïo sóma ólvu güêr-us ês-a.
I-NOM.sg that-GEN.sg in.comparison.to more heavy-GEN.sg be-IND

But a number of the current sentences involve the comparison of two
sentences, e.g., I sat at my desk longer than the day has hours, or, I
did worse on my midterm for this class than I've ever done before.

I don't know how to grammaticalize this type of comparison.  The
textbooks of Ancient Greek that I own are of no help.

Any suggestions?

Charlie
http://wiki.frath.net/Senjecas

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