PHP Primeras 20 palabras

function limit_text($text, $limit) {
    if (str_word_count($text, 0) > $limit) {
        $words = str_word_count($text, 2);
        $pos   = array_keys($words);
        $text  = substr($text, 0, $pos[$limit]) . '...';
    }
    return $text;
}

echo limit_text('Hello here is a long sentence that will be truncated by the', 5);
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