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Mr Chavez underlined the billions of dollars of aid Venezuela is ploughing into Bolivia's economy at a time when the US is reducing its contributions.
US President George W Bush has avoided discussing his rival's regional trip during his own visit to Latin America.
[Source : BBC NEWS | Americas | Chavez launches biting US attack ]
What does `ploughing into' mean in this sentence?
Also, What does `reducing its contributions' refer to here?