Check out example codes for "html underline". It will help you in understanding the concepts better.
Code Example 1
<!-- Using 'u' tag we can draw underline below the text in HTML -->
<p>Hello all <u>Welcome here !!!</u></p>
Code Example 2
Ex. Underline word "parragraph" using 'u' tag:
<p>This is a <u>parragraph</u>.</p>
Code Example 3
<p>This text is not underlined</p><u>This text is underlined</u>
Code Example 4
<p>This is a <u>parragraph</u>.</p>
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