They certainly know what they are doing.
1	They	they	PRON	PRP	Case=Nom|Number=Plur|Person=3|PronType=Prs	3	nsubj	3:nsubj	_
2	certainly	certainly	ADV	RB	_	3	advmod	3:advmod	_
3	know	know	VERB	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	0	root	0:root	_
4	what	what	PRON	WP	PronType=Int	7	obj	7:obj	_
5	they	they	PRON	PRP	Case=Nom|Number=Plur|Person=3|PronType=Prs	7	nsubj	7:nsubj	_
6	are	be	AUX	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	7	aux	7:aux	_
7	doing	do	VERB	VBG	Tense=Pres|VerbForm=Part	3	ccomp	3:ccomp	SpaceAfter=No
8	.	.	PUNCT	.	_	3	punct	3:punct	_
