Breakdown of Jeg synes at opførslen er dårlig hvis han også glemmer svaret.
jeg
I
være
to be
han
he
også
also
Questions & Answers about Jeg synes at opførslen er dårlig hvis han også glemmer svaret.
Why does også come before the verb glemmer?
This highlights the main rule for word order in subordinate clauses! In a normal main sentence, you would say han glemmer også (he also forgets). But because this part of the sentence is a subordinate clause introduced by hvis (if), central adverbs like også, ikke, and altid are forced to jump in front of the verb.
Why use synes here instead of tror for "think"?
You use synes when expressing a subjective opinion or a personal judgment. Since the speaker is evaluating the behavior as bad, synes is the right choice. You would use tror if you were just guessing a fact or expressing a belief, like "I think he is at home."
The dictionary form of "behavior" is opførsel. Why is it spelled opførslen here?
This is the definite form meaning "the behavior". When a Danish noun ends in -el, the e in that ending usually drops out when you add the definite suffix -en. So opførsel + -en shrinks down to opførslen to make it roll off the tongue easier.
Are there two subordinate clauses in this sentence?
Yes! The main clause is just Jeg synes (I think). Everything after that is subordinate. at opførslen er dårlig is a subordinate clause acting as the object of your opinion, and hvis han også glemmer svaret is another subordinate clause explaining the condition.