Translation:Yesterday I worked more than eight hours.
Mmmm, I'm not entirely sure on how to say "I've been working" (something like "Ik ben aan het werken geweest" I guess) (as a different construction to that of "I've worked"/"ik heb gewerkt") in Dutch, but anyway, as in the example the time frame to which the sentence is referring is specific, it wouldn't quite work, in English you have to use the Simple Past tense in such occasions.
That what i found about that topic https://www.startpagina.nl/v/taal/vraag/73284/zeggen-twee-uur-geleden-twee/ and In Dutch, the units of measure are rarely used in the plural (except some in time.) 1 Meter, 2 meter - 1 liter, 2 liter - 1 kilo, 2 kilo - 500 gram The time units ending in -R (het) kwartier ('quarter, 15 minutes') - (het) uur ('hour') and (het) jaar ('year') are often used as both singular and plural; the regular plurals are uren and jaren - kwartier as '15 minutes' does not have a plural. 'Quarter' as '25 cents' is (het) kwartje Drie kwartier ('[3 quarters] 45 minutes') - vier uur ('4 hours') - vijf jaar ('5 years') https://www.heardutchhere.net/plurals.html
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I worked over 8 hours, I worked more than 8 hours, I worked for more than eight hours, I worked 8 plus hours, I worked for over 8 hours...there's no algorithm that'll stuff them all in ahead of time, while leaving out the even more numerous wrong answers.
It wouldn't be accepted because it is clunky sounding English. When we say x>y in reference to time, it's always 'more than' not 'over.' With time, 'over' means something happens throughout a given amount of time. In this case, let how similar Dutch is to English and just translate 'meer dan' word-for-word and you won't go wrong.
The first verb (heb) is in second position. Present perfect (and most tenses other than simple present and simple past) puts the verb marking the tense in the "normal" verb position, and the main verb (gewerkt) at the end. (Although there are clauses that can come after the emd-verb, sometimes)