At the time, he was still a proponent of Noam Chomsky's theory of generative grammar during its earliest transformational grammar phase.
1	At	at	ADP	IN	_	3	case	3:case	Discourse=context-background:27->28:1|XML=<date notBefore:::"1961" notAfter:::"1971">
2	the	the	DET	DT	Definite=Def|PronType=Art	3	det	3:det	_
3	time	time	NOUN	NN	Number=Sing	9	obl	9:obl:at	SpaceAfter=No|XML=</date>
4	,	,	PUNCT	,	_	3	punct	3:punct	_
5	he	he	PRON	PRP	Case=Nom|Gender=Masc|Number=Sing|Person=3|PronType=Prs	9	nsubj	9:nsubj	Entity=(1-person-giv:act-cf1*-1-ana-Charles_J._Fillmore)
6	was	be	AUX	VBD	Mood=Ind|Number=Sing|Person=3|Tense=Past|VerbForm=Fin	9	cop	9:cop	_
7	still	still	ADV	RB	Degree=Pos	9	advmod	9:advmod	_
8	a	a	DET	DT	Definite=Ind|PronType=Art	9	det	9:det	Entity=(1-person-giv:act-cf1*-2-pred-Charles_J._Fillmore
9	proponent	proponent	NOUN	NN	Number=Sing	0	root	0:root	_
10	of	of	ADP	IN	_	14	case	14:case	_
11	Noam	Noam	PROPN	NNP	Number=Sing	14	nmod:poss	14:nmod:poss	Entity=(55-abstract-new-cf2-2,4-coref(56-person-new-cf3-1,2-sgl-Noam_Chomsky|XML=<ref>
12-13	Chomsky's	_	_	_	_	_	_	_	_
12	Chomsky	Chomsky	PROPN	NNP	Number=Sing	11	flat	11:flat	XML=</ref>
13	's	's	PART	POS	_	11	case	11:case	Entity=56)
14	theory	theory	NOUN	NN	Number=Sing	9	nmod	9:nmod:of	_
15	of	of	ADP	IN	_	17	case	17:case	_
16	generative	generative	ADJ	JJ	Degree=Pos	17	amod	17:amod	Entity=(57-abstract-new-cf4-2-coref|XML=<ref>
17	grammar	grammar	NOUN	NN	Number=Sing	14	nmod	14:nmod:of	Entity=57)55)1)|XML=</ref>
18	during	during	ADP	IN	_	23	case	23:case	_
19	its	its	PRON	PRP$	Case=Gen|Gender=Neut|Number=Sing|Person=3|Poss=Yes|PronType=Prs	23	nmod:poss	23:nmod:poss	Entity=(58-abstract-new-cf5-5-sgl(55-abstract-giv:act-cf2-1-ana)
20	earliest	early	ADJ	JJS	Degree=Sup	23	amod	23:amod	_
21	transformational	transformational	ADJ	JJ	Degree=Pos	22	amod	22:amod	Entity=(59-abstract-new-cf6-2-coref|XML=<ref>
22	grammar	grammar	NOUN	NN	Number=Sing	23	compound	23:compound	Entity=59)|XML=</ref>
23	phase	phase	NOUN	NN	Number=Sing	9	nmod	9:nmod:during	Entity=58)|SpaceAfter=No
24	.	.	PUNCT	.	_	9	punct	9:punct	_
