Try - typically something quick and low stakes. There is not necessarily a clear success/failure. You can try a new hair style or a new sport or new food. Strive - To strive for something is a bigger investment and typically means you will have to deal with setbacks. You strive to get into medical school or a government policy may strive to eliminate poverty. There is a sense of a long running effort to achieve the desired outcome. Attempt - Very commonly a noun not a verb. As a verb, it is often a small bit of effort that fails. "I attempted to score a goal" suggests (but doesn't strictly require) that you failed. Similar to try in that it is typically small and very quick without emphasis on a continuing process. Often used in multiples. "it took me five attempts before i succeeded" Endeavor - I almost always hear this as a noun. As with strive, often on very large goals. "To have humans live on Mars is an ambitious endeavor."