The infinite
The infinite -n is the only productive inflectional suffix in Siglisc.
Phonologically it's actually a clitic because it doesn't shorten the preceding vowel, like nasals usually do.
ga [ga:] 'goes', gan [ga:n] 'to go' instead of *[gan]
Syntactically it's though a suffix.
Ek meg [met]n an [slap]n. 'I'd like to eat and sleap.' instead of *
Ek meg [met an slap]n.
Historically the infinite derives from three infinite verb forms: the Germanic infinitive (German seh-en 'to see'), the Germanic perfect participle of strong verbs (German ge-seh-en 'seen'), and Germanic present participle (German seh-ende 'seeing). When the prefix ge- was lost, the forms merged. Because the infinite is the only infinite verb form in Siglisc, I call it generally the infinite, isntead of the infinitive.
Syntactically they are the same form:
Ek [vehll an hau] rysn szu Amerika. 'I wanted and did travel to America.' lit. [wanted and have] travel(ed)
The past infinite
-n is quite cliticlike. So it can be added to simple past forms of strong verbs. That's common with ablaut verbs but questionable with k->t verbs. Weak verbs form the past infinite prefrastically (haun + the infinite).
kom 'comes' -> komn 'to come' - kam 'came' -> kamn 'to have come'
mak 'makes' -> makn 'to make' - mat 'made' -> ?matn 'to have made'
Hi mosz kamn red. 'He must have come already.'
Ek mosz haun sin hi red. 'I must have seen him already.'
Infinitive (complemental)
use
Most verbs take the pure infinite
Ek kom otgan. 'I should leave.'
Ek kan sprekn siglisc. 'I can speak Siglisc.'
Ek sca skrynv en buk. 'I will write a book.'
Verbs of motion need preposition szu 'to'
Ek ja szu scemn. 'I went to swim.'
Ek vell szu scemn. 'I want to [go to] swim.'
Szu is also used to express purpose
Ek hau keubn en kak, szu makn dau loszi. 'I bought a cake, to make you happy.'
Ek hau naui geld szu it. 'I have no money to use.'
Durativity of action can be emphasized with preposition in 'in'.
Ek hau sin dau slapn. 'I saw you sleep.'
Ek hau sin dau in slapn. 'I have seen you sleeping.'
Edit: 'Is able to' is kan
'Is allowed to' is kan + in
Dau kan gyn him.
' You can walk home.'
Dau kan in gyn him.
'You are allowed to walk home.'
I think some kind of a 'from' preposition can also be used in some constructions.
Action nominal use
In principle the -n form of any verb can be used as an abstract noun, like English -ing or German-en. If the abstract noun of the verb in question is formed by other means, the -n form is rare in that use.
liv 'lives' lyv 'life'
The infinite can though take attributes
Tritn o catscin is insc frendi. 'Kicking of kittens is not nice.' Lit. Kicking of kittens
Brutal tritn o catscin 'brutal kicking of kittens'
The action nominal, being syntactically a noun, cannot have a direct object or by-agent.
Attributive use (participle?)
Siglisc does not have real adjectival participles. A action nominal can though be joined with a noun with preposition o 'of'. Their orientation and tense however depends of natural semantics, lexicalization, and context, so it's not very productive.
Cips o grilln 'grilled chips' Lit. chips of grilling
Compounds can also be formed:
Grilln-cips 'grill chips'
slapn-zyd 'sleeping time'
Converb (adverbial)
use
I'm not sure how the finite should behave in those functions. I have two alternatives.
1. Like English -ing gerund. - simultaneous action
Writing my essay, I cannot go outdoors.
2. Like Swedish supine. That use would derive from the perfect participle. - anterior action
När jag skrivit min uppsats, kan jag gå ut. 'When I [have] written my essay, I can go outdoors.'