use Modern::Perl;
use Lingua::StopWords qw( getStopWords );

my $str  = "is that true";
my $str1 = "this is from presentation";
my $str2 = "to create";

say removeStopWords( eval $_ ) for qw{$str $str1 $str2};

sub removeStopWords {
    my $stopWords = getStopWords('en');
    join ' ', grep { !$stopWords->{$_} } split ' ', $_[0];
}

##</code><code>##

true
presentation
create