intervene

interfere, intervene, meddle

这些动词均含“干涉，干预”之意。
interfere: 侧重指无权或未获允许而妨碍、阻扰、干涉他人之事。
intervene: 书面用词，指介入争端，进行调停，也指干涉他人之事。
meddle: 指干预与自己毫不相关的事或不属于自己职责范围的事，隐含未经许可或授权。可与interfere换用。

动词 intervene:

1. get involved, so as to alter or hinder an action, or through force or threat of force
   同义词：step in, interfere, interpose
2. be placed or located between other things or extend between spaces and events
3. occur between other event or between certain points of time

1. I am powerless to intervene in the matter.
   我对调停此事无能为力。
2. I intervened on her behalf to try to get the decision changed.
   我为她力争，以求改变决定。
3. I will come if nothing intervenes.
   假若没有别的事，我一定来。
4. I was alone during intervening years.
   这期间的若干年里，我一直一个人。

in.ter.vene

v.intr.（不及物动词）
in.ter.vened,in.ter.ven.ing,in.ter.venes
To come, appear, or lie between two things:
插进：来到、出现于或位于两个物体之间：
例句：
You can`t see the lake from there because the house intervenes.
在那儿你无法看到湖，因为有房子介于其间

To come or occur between two periods or points of time:
发生于其间：来到或发生于两段时间或两个时间点之间：
例句：
A year intervened between the two dynasties.
两个朝代之间隔了一年

To occur as an extraneous or unplanned circumstance:
干扰：作为一无关的或计划外的情形发生：
例句：
He would have his degree by now if his laziness hadn`t intervened.
如果不是他的懒惰干扰的话，现在他已经获得学位了

To come in or between so as to hinder or alter an action:
斡旋：来到…中间或以阻碍或改变一行动：
例句：
intervened to prevent a fight.
调停以防止打架

To interfere, usually through force or threat of force, in the affairs of another nation.
干涉：干涉他国事务，通常以武力或威胁手段
Law To enter into a suit as a third party for one`s own interests.
【法律】 参加诉讼：出于自己的利益参加诉讼

来源：
Latin intervenore
拉丁语 intervenore
inter- [inter-]
inter- [前缀，表.在…之间.]
venore [to come] * see g w3-
venore [来到] *参见 g w3-

【引伸】
in.terve.nor 或
in.terven.er
n.（名词）
in.terven.tion
in.terven.tional
adj.（形容词）