Their selection is random, so what they have on a given week might never be available again at the store.
1	Their	their	PRON	PRP$	Case=Gen|Number=Plur|Person=3|Poss=Yes|PronType=Prs	2	nmod:poss	2:nmod:poss	_
2	selection	selection	NOUN	NN	Number=Sing	4	nsubj	4:nsubj	_
3	is	be	AUX	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	4	cop	4:cop	_
4	random	random	ADJ	JJ	Degree=Pos	0	root	0:root	SpaceAfter=No
5	,	,	PUNCT	,	_	4	punct	4:punct	_
6	so	so	ADV	RB	_	17	advmod	17:advmod	_
7	what	what	PRON	WP	PronType=Int	17	nsubj	17:nsubj	_
8	they	they	PRON	PRP	Case=Nom|Number=Plur|Person=3|PronType=Prs	9	nsubj	9:nsubj	_
9	have	have	VERB	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	7	acl:relcl	7:acl:relcl	_
10	on	on	ADP	IN	_	13	case	13:case	_
11	a	a	DET	DT	Definite=Ind|PronType=Art	13	det	13:det	_
12	given	give	VERB	VBN	Tense=Past|VerbForm=Part	13	amod	13:amod	_
13	week	week	NOUN	NN	Number=Sing	9	obl	9:obl:on	_
14	might	might	AUX	MD	VerbForm=Fin	17	aux	17:aux	_
15	never	never	ADV	RB	_	17	advmod	17:advmod	_
16	be	be	AUX	VB	VerbForm=Inf	17	cop	17:cop	_
17	available	available	ADJ	JJ	Degree=Pos	4	parataxis	4:parataxis	_
18	again	again	ADV	RB	_	17	advmod	17:advmod	_
19	at	at	ADP	IN	_	21	case	21:case	_
20	the	the	DET	DT	Definite=Def|PronType=Art	21	det	21:det	_
21	store	store	NOUN	NN	Number=Sing	17	obl	17:obl:at	SpaceAfter=No
22	.	.	PUNCT	.	_	4	punct	4:punct	_
