To need something for a particular purpose or result.

• To call for as necessary or essential.

为达到某目的而需要某物。

• 作为必要或不可缺少的条件。

To make something obligatory by rule, law, or authority.

• To demand that someone do something as a condition.

由规则、法律或权威规定某事为义务。

• 要求某人必须做某事，作为条件。

To ask for something in a formal or polite way.

• Formal or dated.

正式或礼貌地请求某物。

• 正式或较旧的用法。