How to make text stored in a function bold while displaying

Question

<? php
$row='hello' ;
echo "hello". $row;
? > in this I want $row value in bold how to do it

Answer 1

<?php
$row='hello';
echo "hello<b>". $row ."</b>";
?>

Answer 2

Using <b></b> tags surrounding the text

Answer 3

Thanku very much Anna

Answer 4

If I write
echo "hello". <b>$row</b>;
Syntax error unexpected '<' is the error I got