pr6*-SentenceExtractor.php

<?php
$textInput = "This is my cat!Is this ! And this is my dog. We happily live in Paris – the most beautiful city in the world! Isn’t it great? Well it is :)    ";
$word = "is";

$textArr = [];
$sentence = "";
for ($i = 0; $i <strlen($textInput); $i++){

    $ch = $textInput[$i];
    $sentence .=$ch;
    if ($ch == "." || $ch == "?" || $ch == "!"){
        $textArr[] = $sentence;
        $sentence = "";
    }
}
//var_dump($sentence);
foreach ($textArr as $snt){

    $sntArr = str_word_count($snt, 1);
    $sntArr_len = count($sntArr);

    for ($ii = 0; $ii < $sntArr_len; $ii++){

        if ($sntArr[$ii] ==  $word){

            echo $snt . "\n";
            break;
        }
    }
}

?>