Английский словарь американских идиом - pitch in

{v.}, {informal} 1. To begin something with much energy; start work eagerly. * /Pitch in and we will finish the job as soon as possible./ 2. To give help or money for something; contribute. * /Everyone must pitch in and work together./ * /We all pitched in a quarter to buy Nancy a present./ Syn.: CHIP IN. Compare: FALL TO.