Simple past tense and past participle of improve.(verb)
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Use "improved" in a sentence
"Experiments with vertical mulches in gently sloping Vertisols in semiarid India have shown that sorghum stubble packed in trenches 15 cm (6 in) wide improved water infiltration and produced larger yields of grain and straw of an improved variety of sorghum, especially in years of drought. 26 Vertical mulch in trenches 30 cm (12 in) deep and 2 m (6.5 ft) apart gave 25 times more grain yield and 2 times more straw yield than the areas without vertical mulches in a very dry year."
"The term "improved offerings" should mean more for your money, not more of your money."
"New means smallered and improved is code for price increase."