・50%ずつ並べた場合の例
<dl class="dl_table">
  <dt>項目1</dt><dd>内容1</dd>
  <dt>項目2-1<br>項目2-2</dt><dd>内容2</dd>
  <dt>項目3</dt><dd>内容3</dd>
  <dt>項目4</dt><dd>内容4-1<br>内容4-2<br>内容4-3<br>内容4-4</dd>
</dl>
/* ブラウザの初期設定をクリア */
dl,dt,dd {
  margin: 0;
  padding: 0;
}

.dl_table {
  background-color: #FFF;
  border-top: 1px solid #E4E4E4;
  border-left: 1px solid #E4E4E4;
  margin: 20px;
  width: 300px;
  display: flex;
  flex-wrap: wrap;
}
.dl_table dt {
  background-color: #FBFBFB;
  font-weight: bold;
}
.dl_table dt,
.dl_table dd {
  padding: 15px;
  width: 50%;
  box-sizing: border-box;
  border-right:  1px solid #E4E4E4;
  border-bottom: 1px solid #E4E4E4;
}

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