pitch：n. 球场；程度；音调；推销；投掷；街头商贩摊位；沥青；树脂；松脂。v. 投；颠簸；搭帐篷；定调；推销；用沥青覆盖。
pitch in加入，投入；pitch out开除，逐出。

【例句】
If I really pitch in, I may be able to finish my paper before the deadline.
如果我加紧工作,我也许就能在限期以前完成我的论文。

They pitched two members out for failing to pay the money they owed.
他们把两名因未交纳所欠款项的会员开除。