(-pp-) ●step into the ˈbreachto do sb's job or work when they are suddenly or unexpectedly unable to do it
临时顶缺；代班●step into sb's ˈshoesto continue a job or the work that sb else has started
接替某人工作
●ˌstep aˈside/ˈdownto leave an important job or position and let sb else take your place
让位；辞去职位◆James Nellist will step down as chairman at the end of this year.
詹姆斯 • 内尔李斯特将在年底辞去主席职务。  ➡  see note at resign ●ˌstep ˈinto help sb in a dispute or difficult situation
斡旋；调停◆The bank stepped in to rescue the company with a large loan.
这家银行出面借出了一大笔资金以解救这家公司走出困境。●ˌstep ˈup sthto increase the amount, speed, etc. of sth
增加，提高（数量、速度等）◆We need to step up production to increase stocks.
我们必须增加产量以提高库存。HELP A noun goes after up, but a pronoun goes between the verb and up.
名词接在 up 之後，而代词则出现在动词和 up 之间。