I didn't understand why he couldn't see that.
1	I	I	PRON	PRP	Case=Nom|Number=Sing|Person=1|PronType=Prs	4	nsubj	4:nsubj	Discourse=attribution-negative:184->185:0|Entity=(13-person-giv:act-cf1*-1-ana)
2-3	didn't	_	_	_	_	_	_	_	_
2	did	do	AUX	VBD	Mood=Ind|Number=Sing|Person=1|Tense=Past|VerbForm=Fin	4	aux	4:aux	_
3	n't	not	PART	RB	Polarity=Neg	4	advmod	4:advmod	_
4	understand	understand	VERB	VB	VerbForm=Inf	0	root	0:root	_
5	why	why	SCONJ	WRB	PronType=Rel	4	obj	4:obj	Discourse=evaluation-comment:185->183:0
6	he	he	PRON	PRP	Case=Nom|Gender=Masc|Number=Sing|Person=3|PronType=Prs	9	nsubj	9:nsubj	Entity=(14-person-giv:inact-cf3-1-ana)
7-8	couldn't	_	_	_	_	_	_	_	_
7	could	could	AUX	MD	VerbForm=Fin	9	aux	9:aux	_
8	n't	not	PART	RB	Polarity=Neg	9	advmod	9:advmod	_
9	see	see	VERB	VB	VerbForm=Inf	5	advcl:relcl	5:advcl:relcl	XML=<hi rend:::"italic"></hi>
10	that	that	PRON	DT	Number=Sing|PronType=Dem	9	obj	9:obj	Entity=(145-event-giv:act-cf2-1-coref)|SpaceAfter=No
11	.	.	PUNCT	.	_	4	punct	4:punct	_
