$_ = "Tim created the ...";

while ( /\bit (.*?)[.?!]/ig ) {
    print "\n$1\n";
}

##</code><code>##

while (<>) {
    while ( /\bit (.*?)[.?!]/ig ) {
        print "\n$1\n";
    }
}

##</code><code>##

 perl test.pl test.txt