Learn Icelandic: Þeir sleppa alltaf formlegheitunum á fundunum. - They always skip the formalities at the meetings.

The verb sleppa governs the dative case when it means "to skip", "to omit", or "to let go of" something. Since they are skipping the formalities, formlegheitunum is the dative object. Note that when sleppa means "to escape", it is an intransitive verb and doesn't take an object at all.

How does the word formlegheitunum break down?

The base word is formlegheit (formality), formed from the adjective formlegur (formal) and the neuter suffix -heit (similar to "-ity" or "-ness"). Because it is the dative plural object of the verb, it takes the neuter dative plural definite ending -unum.

Why do we use the preposition á instead of í for "at the meetings"?

In Icelandic, you use á for events, gatherings, or scheduled activities. Just as you are á fundi (at a meeting), you would also be á tónleikum (at a concert) or á æfingu (at a practice).

Why does á govern the dative case for fundunum here?

The preposition á controls the dative case when it describes a static location or situation, answering the question "where?" (hvar?). If the sentence involved movement towards the meetings, answering "where to?" (hvert?), á would control the accusative case.