how to underline word in css code example

Example 1: text-decoration css

h1 {
  text-decoration: overline;
}

h2 {
  text-decoration: line-through;
}

h3 {
  text-decoration: underline;
}

h4 {
  text-decoration: underline overline;
}

Example 2: html underline tag

Ex. Underline word "parragraph" using 'u' tag:

<p>This is a <u>parragraph</u>.</p>