Over time, construction grammar developed into a research area of its own, and a number of variants have been proposed over the years by different researchers.
1	Over	over	ADP	IN	_	2	case	2:case	Discourse=joint-other_m:77->64:1
2	time	time	NOUN	NN	Number=Sing	6	obl	6:obl:over	SpaceAfter=No
3	,	,	PUNCT	,	_	2	punct	2:punct	_
4	construction	construction	NOUN	NN	Number=Sing	5	compound	5:compound	Entity=(133-abstract-giv:act-cf1*-2-coref
5	grammar	grammar	NOUN	NN	Number=Sing	6	nsubj	6:nsubj	Entity=133)
6	developed	develop	VERB	VBD	Mood=Ind|Number=Sing|Person=3|Tense=Past|VerbForm=Fin	0	root	0:root	_
7	into	into	ADP	IN	_	10	case	10:case	_
8	a	a	DET	DT	Definite=Ind|PronType=Art	10	det	10:det	Entity=(157-abstract-new-cf4-3-sgl
9	research	research	NOUN	NN	Number=Sing	10	compound	10:compound	_
10	area	area	NOUN	NN	Number=Sing	6	obl	6:obl:into	_
11	of	of	ADP	IN	_	13	case	13:case	_
12	its	its	PRON	PRP$	Case=Gen|Gender=Neut|Number=Sing|Person=3|Poss=Yes|PronType=Prs	13	nmod:poss	13:nmod:poss	Entity=(133-abstract-giv:act-cf1*-1-ana)
13	own	own	ADJ	JJ	Degree=Pos	10	nmod	10:nmod:of	Entity=157)|SpaceAfter=No
14	,	,	PUNCT	,	_	22	punct	22:punct	_
15	and	and	CCONJ	CC	_	22	cc	22:cc	Discourse=joint-list_m:78->77:0
16	a	a	DET	DT	Definite=Ind|PronType=Art	17	det	17:det	Bridge=133<158|Entity=(158-abstract-acc:inf-cf2-2-sgl
17	number	number	NOUN	NN	Number=Sing	22	nsubj:pass	22:nsubj:pass	_
18	of	of	ADP	IN	_	19	case	19:case	_
19	variants	variant	NOUN	NNS	Number=Plur	17	nmod	17:nmod:of	Entity=158)
20	have	have	AUX	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	22	aux	22:aux	_
21	been	be	AUX	VBN	Tense=Past|VerbForm=Part	22	aux:pass	22:aux:pass	_
22	proposed	propose	VERB	VBN	Tense=Past|VerbForm=Part|Voice=Pass	6	conj	6:conj:and	_
23	over	over	ADP	IN	_	25	case	25:case	_
24	the	the	DET	DT	Definite=Def|PronType=Art	25	det	25:det	_
25	years	year	NOUN	NNS	Number=Plur	22	obl	22:obl:over	_
26	by	by	ADP	IN	_	28	case	28:case	_
27	different	different	ADJ	JJ	Degree=Pos	28	amod	28:amod	Entity=(159-person-new-cf3-2-sgl
28	researchers	researcher	NOUN	NNS	Number=Plur	22	obl:agent	22:obl:agent	Entity=159)|SpaceAfter=No
29	.	.	PUNCT	.	_	6	punct	6:punct	_
