The agency says international relief agencies also have pitched in. [VERB PREP.]

该机构说国际救援机构也提供了支援。

Cartoonists have pitched in with their favourites from their own and other hands. [VERB PREP. with noun]

漫画家拿出了他们最喜爱的出自自己和他人之手的作品。

The entire company pitched in to help. [VERB PREP. to-infinitive]

公司上下都协力相助。