Dependent vs. independent verb forms

[Maria Koptjevskaja Tamm]

Dear colleagues, I am interested in the different ways languages can
acquire their distinctions between finite vs. non-finite or
independent vs. dependent verb forms, i.e. distinctions between those
verb forms that can be used as the main predicate in independent
clauses and those that cannot (at least, not in the normal case). So
far I know of the three following main sources for such splits:

S1. In some cases, dependent verb forms originate as words belonging
to other word classes, but gradually join the verbal paradigm - e.g.,
participles from deverbal adjectives and nominalizations from
deverbal nouns.

S2. In other cases, dependent forms are leftovers, residues or
fossilized forms of older dependent verb forms that, in one or
another way, have been trapped in various syntactic environments ­
e.g., infinitives as locative / directional cases of nominalizations,
and converbs as locative cases of nominalizations or some particular
forms of participles.

S3. Sometimes the original forms are older independent forms ­ when
splits between independent and dependent verb forms arise as a result
of gradual spreading of new grammatical phenomena (primarily
tense-aspect-mood) across different types of constructions involving
verbs. Bybee, Perkins & Pagliuca (1994) mention the cases of
Armenian, Cairene Arabic and Spanish, in which subjunctives (i.e.,
forms typically used in subordinate clauses) have originated from
older indicatives.

In this connection I would need your help with the following questions:

Q1: Do you know of any other ways by which languages can acquire
distinctions between independent and dependent verb forms?

Q2: Do you know of any sources which would trace the history of
"non-verbal" words (such as deverbal adjectives and nouns, apart from
English gerunds) being gradually incorporated into the verbal
paradigm, or at least suggesting a plausible scenario?

Q3: Do you know of any other S3-cases apart from Armenian, Cairene
Arabic and Spanish mentioned above? Can gradual spreading of other
grammatical phenomena apart from tense-aspect-mood lead to
asymmetries between verb forms used in independent / main clauses and
in dependent ones ­ e.g., agreement?

Needless to say, I would be extremely grateful for any advices!!!
All the best to all of you,
--
Maria Koptjevskaja Tamm
Office: Dept. of linguistics, Stockholm university
106 91 Stockholm, Sweden
Tel.: +46-8-16 26 20
http://www.ling.su.se/staff/tamm

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