div {
width: 400px;
border: 1px solid #000000;
margin: 2em 0;
}
.ex1 {white-space: normal;}
.ex2 {white-space: nowrap;}
.ex3 {white-space: pre;}
.ex4 {white-space: pre-wrap;}
.ex5 {white-space: pre-line;}
<!DOCTYPE html>
<html lang="ko">
<head></head>
<body>
<h1>white-space</h1>
<div class="ex1"><b>normal</b><br> Once when I was six years old I saw a magnificent picture in a book, called True Stories from Nature, about the primeval forest.</div>
<div class="ex2"><b>norwrap</b><br> Once when I was six years old I saw a magnificent picture in a book, called True Stories from Nature, about the primeval forest.</div>
<div class="ex3"><b>pre</b><br> Once when I was six years old I saw a magnificent picture in a book, called True Stories from Nature, about the primeval forest.</div>
<div class="ex4"><b>pre-wrap</b><br> Once when I was six years old I saw a magnificent picture in a book, called True Stories from Nature, about the primeval forest.</div>
<div class="ex5"><b>pre-line</b><br> Once when I was six years old I saw a magnificent picture in a book, called True Stories from Nature, about the primeval forest.</div>
</body>
</html>