改变英语单词是change。change的例句：His doctor increased the dosage but did not change to a different medication（他的医生加大了剂量，不过没有换药）。

change的例句：The ambassador appealed for a change in US policy（大使呼吁美国在政策上作出改变）；We are trying to detect and understand how the climates change（我们正努力探寻并理解气候是如何变化的）。