<h1>3. <code> word-break: break-all;</code></h1>
<p class="breakAll  narrow"> This is a long and Supercalifragilisticexpialidocious sentence. 贾宝玉病加重，直至奄奄一息，癞头僧持通灵宝玉引他入太虚幻境变形的真如福地梦中。</p> 

.narrow {
    padding: 5px;
    border: 1px solid;
    width: 8em;
}

.normal {
    word-break: normal;
}

.breakAll {
    word-break: break-all;
}

.keep {
    word-break: keep-all;
}

.break-word{
  overflow-wrap: break-word;
}

body{margin:2rem; line-height:1.6rem;}

h1{font-weight:bold; font-size:2rem;margin: 1rem 0}