<ul class="nav">
  <li class="nav-item"><a class="nav-link active" href="#">Active</a></li>
  <li class="nav-item"><a class="nav-link" href="#">Link</a></li>
  <li class="nav-item"><a class="nav-link" href="#">Link</a></li>
  <li class="nav-item"><a class="nav-link disabled" href="#">Disabled</a></li>
</ul>

<ul class="nav flex-column">
  <li class="nav-item"><a class="nav-link active" href="#">Active</a></li>
  <li class="nav-item"><a class="nav-link" href="#">Link</a></li>
  <li class="nav-item"><a class="nav-link" href="#">Link</a></li>
  <li class="nav-item"><a class="nav-link disabled" href="#">Disabled</a></li>
</ul>

<ul class="nav nav-pills">
  <li class="nav-item"><a class="nav-link active" href="#">Active</a></li>
  <li class="nav-item"><a class="nav-link" href="#">Link</a></li>
  <li class="nav-item"><a class="nav-link" href="#">Link</a></li>
  <li class="nav-item"><a class="nav-link disabled" href="#">Disabled</a></li>
</ul>

<ul class="nav nav-pills nav-fill">
  <li class="nav-item"><a class="nav-link active" href="#">Active</a></li>
  <li class="nav-item"><a class="nav-link" href="#">Longer nav link</a></li>
  <li class="nav-item"><a class="nav-link" href="#">Link</a></li>
</ul>