String in PHP heredoc and nowdoc

CODE:

String in PHP heredoc and nowdoc
<?php

$beVerb = "is";
$sentence1 = 'My name $beVerb Jim';
echo "Sentence 1 in single quotation";
echo "<br>";
echo $sentence1;
echo "<br>";
$sentence2 = "My name $beverb Jim";
echo "Sentence 1 in single quotation<br>";
echo $sentence2;
echo "<br>PHP HERE DOC EXAMPLE<br>";
$str = <<<tom
the beverb i used $beVerb 
another test
'this is multiple test'
and the be verb is $beVerb
another "test"
tom;

echo $str;

echo "<br>PHP NOW DOC EXAMPLE<br>";
$str = <<<'tom'
the beverb i used $beVerb 
another test
'this is multiple test'
and the be verb is $beVerb
another "test"
tom;

echo $str;

?>

OUTPUT:

Sentence 1 in single quotation
My name $beVerb Jim
Sentence 1 in single quotation
My name Jim
PHP HERE DOC EXAMPLE
the beverb i used is another test 'this is multiple test' and the be verb is is another "test"
PHP NOW DOC EXAMPLE
the beverb i used $beVerb another test 'this is multiple test' and the be verb is $beVerb another "test"