COOPERATE

[verb] [I] - to act or work together for a particular purpose, or to help someone willingly when help is requestedI find it very hard to dress my two-year-old when she just refuses to cooperate.The two companies have cooperated for the past several years in joint ventures.The Spanish authorities cooperated with the British police in finding the terrorists.He said that he had cooperated (fully/closely) with the government in its investigation.(humorous) We're going to have a picnic on Saturday, if the weather cooperates (= is suitable).