Breakdown of Við höfum aldrei siglt á bátnum þínum.
við
we
á
onto / on / in (static location) / on (a day of the week)
þinn
your (m, f, n: þinn, þín, þitt)
báturinn
the boat
Questions & Answers about Við höfum aldrei siglt á bátnum þínum.
Why is the adverb aldrei placed right after höfum?
In the present perfect tense, short adverbs like aldrei (never), alltaf (always), or ekki (not) go directly between the helping verb (höfum) and the main verb (siglt). This matches the English word order perfectly: we have never sailed.
What form of the verb is siglt here?
It is the supine form (the neuter singular past participle) of the verb sigla (to sail). Whenever you use the helping verb hafa (to have) to create the present perfect tense, the main verb must be in this supine form.
Why are the words for your boat (bátnum þínum) in the dative case?
The preposition á takes the dative case when it describes the location where an action takes place, rather than movement towards a new destination. Because the sailing is happening on the boat, it triggers the dative case.
Why does the noun have a the ending (bátnum) if it is followed by your (þínum)?
In Icelandic, when you place a possessive word like þínum after a noun, that noun almost always takes the attached definite article. So you literally say boat-the your (bátnum þínum).