Poderia ter sido causada por_ a queda .
1	Poderia	poder	VERB	V	Mood=Cnd|Number=Sing|Person=3	0	root	_	_
2	ter	ter	VERB	INF	VerbForm=Inf	1	xcomp	_	_
3	sido	ser	AUX	PPT	VerbForm=Part	4	cop	_	_
4	causada	causar,causado	VERB	PPA	Gender=Fem|Number=Sing	2	dep	_	_
5	por_	por_	ADP	PREP	_	7	case	_	_
6	a	a	DET	DA	Gender=Fem|Number=Sing	7	det	_	_
7	queda	queda	NOUN	CN	Gender=Fem|Number=Sing	4	obl	_	_
8	.	.	PUNCT	PNT	_	1	punct	_	_
