Students have their scores measured by four variables: time, speed, stability and accuracy.
1	Students	student	NOUN	NNS	Number=Plur	2	nsubj	2:nsubj	Discourse=elaboration-additional:77->74:1|Entity=(163-person-giv:inact-cf1-1-coref)
2	have	have	VERB	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	0	root	0:root	_
3	their	their	PRON	PRP$	Case=Gen|Number=Plur|Person=3|Poss=Yes|PronType=Prs	4	nmod:poss	4:nmod:poss	Entity=(179-abstract-new-cf4-2-sgl(163-person-giv:act-cf1-1-ana)
4	scores	score	NOUN	NNS	Number=Plur	2	obj	2:obj|5:nsubj:pass:xsubj	Entity=179)
5	measured	measure	VERB	VBN	Tense=Past|VerbForm=Part	2	xcomp	2:xcomp	_
6	by	by	ADP	IN	_	8	case	8:case	_
7	four	four	NUM	CD	NumForm=Word|NumType=Card	8	nummod	8:nummod	Entity=(180-abstract-new-cf2-2-coref
8	variables	variable	NOUN	NNS	Number=Plur	5	obl:agent	5:obl:agent	Entity=180)|SpaceAfter=No
9	:	:	PUNCT	:	_	10	punct	10:punct	_
10	time	time	NOUN	NN	Number=Sing	8	appos	8:appos	Discourse=elaboration-additional:78->77:0|Entity=(180-abstract-giv:act-cf2-1,3,5,7-appos(181-time-new-cf5-1-sgl)|SpaceAfter=No
11	,	,	PUNCT	,	_	12	punct	12:punct	_
12	speed	speed	NOUN	NN	Number=Sing	10	conj	8:appos|10:conj:and	Entity=(159-abstract-giv:inact-cf3-1-coref)|SpaceAfter=No
13	,	,	PUNCT	,	_	14	punct	14:punct	_
14	stability	stability	NOUN	NN	Number=Sing	10	conj	8:appos|10:conj:and	Entity=(182-abstract-new-cf6-1-sgl)
15	and	and	CCONJ	CC	_	16	cc	16:cc	_
16	accuracy	accuracy	NOUN	NN	Number=Sing	10	conj	8:appos|10:conj:and	Entity=(183-abstract-new-cf7-1-sgl)180)|SpaceAfter=No
17	.	.	PUNCT	.	_	2	punct	2:punct	_
