( ( What ( makes ( any ( given plant ) ) ) ) ( ( a weed ) ( ( ( depends , ) ( of ( ( course , ) ( ( on what ) ( you ( ( do and ) ( ( do not ) ( want ( to ( grow ( in ( a ( given space ) ) ) ) ) ) ) ) ) ) ) ) ) . ) ) )
(ROOT (S (SBAR (WHNP (WP What)) (S (VP (VBZ makes) (NP (DT any) (VBN given) (NN plant))))) (NP (DT a) (NN weed)) (VP (VBZ depends) (, ,) (PP (IN of) (NP (NP (NN course)) (, ,) (SBAR (WHPP (IN on) (WHNP (WP what))) (S (NP (PRP you)) (VP (VP (VBP do)) (CC and) (VP (VBP do) (RB not) (VP (VB want) (S (VP (TO to) (VP (VB grow) (PP (IN in) (NP (DT a) (VBN given) (NN space)))))))))))))) (. .)))
What makes any given plant a weed depends, of course, on what you do and do not want to grow in a given space.
(ROOT (S (NP (NP (NNS Plants)) (SBAR (WHNP (WDT that)) (S (VP (VBP grow) (SBAR (WHADVP (WRB where)) (S (NP (PRP you)) (VP (VBP do) (RB n't) (VP (VB want) (NP (PRP them)))))))))) (VP (VBP are) (VP (VBN called) (NP (NNS weeds)))) (. .)))