./concordance.pl plant nanc_nyt94_plant_sents.txt | head -8   

produces:

de_VBP training_VBG new_JJ Ukrainian_JJ     plant    _NN operators_NNS to_TO replace_VB Russi
_NNPS who_WP are_VBP leaving_VBG the_DT     plant    s_NNS in_IN Ukraine_NNP and_CC improving
N and_CC safety_NN procedures_NNS at_IN     plant    s_NNS in_IN both_DT countries_NNS ,_, sa
iet-designed_JJ reactors_NNS at_IN a_DT     plant    _NN in_IN the_DT Czech_NNP Republic_NNP 
er_JJ to_TO pay_VB to_TO make_VB the_DT     plant    _NN safer_JJR ._. 
er_JJ to_TO pay_VB to_TO make_VB the_DT     plant    _NN safer_JJR ._. 
 ,_, ''_'' she_PRP said_VBD ,_, are_VBP     plant    _NN moratoriums_NNS ._. 
_NNS at_IN the_DT Orange_NNP County_NNP     plant    _NN ._. 


for searching through more than one file:

cat nanc* | ./concordance.pl plant - | less

for searching larger contexts:

./concordance.pl plant nanc_nyt94_plant_sents.txt 45 | less

Anoop Sarkar
anoop at cs.sfu.ca