Trees within tree families

Each tree begins with either an $\alpha$ (alpha) or a $\beta$ (beta) symbol, indicating whether it is an initial or auxiliary tree, respectively. Following an $\alpha$ or a $\beta$ the name may additionally contain one of:

I	imperative
E	ergative
N0,1,2	relative clause{position}
G	NP gerund
D	Determiner gerund
pW0,1,2	wh-PP extraction{position}
W0,1,2	wh-NP extraction{position}
X	ECM (eXceptional case marking)

Numbers are assigned according to the position of the argument in the declarative tree, as follows:

0	subject position
1	first argument (e.g. direct object)
2	second argument (e.g. indirect object)

The body of the name consists of a string of the following components, which corresponds to the leaves of the tree. The anchor(s) of the trees is(are) indicated by capitalizing the part of speech corresponding to the anchor.

s	sentence
a	adjective
arb	adverb
be	be
c	relative complementizer
x	phrasal category
d	determiner
v	verb
lv	light verb
conj	conjunction
comp	complementizer
it	it
n	noun
p	preposition
to	to
pl	particle
by	by
neg	negation

As an example, the transitive declarative tree consists of a subject NP, followed by a verb (which is the anchor), followed by the object NP. This translates into $\alpha$nx0Vnx1. If the subject NP had been extracted, then the tree would be $\alpha$W0nx0Vnx1. A passive tree with the by phrase in the same tree family would be $\alpha$nx1Vbynx0. Note that even though the object NP has moved to the subject position, it retains the object encoding (nx1).