1.风险：It is a noun in Chinese. It means a hazard or risk which probably occur. ex.If you want to do so ,there will be some "风险"。 ex.We will take a big "风险" to do this surgery。 2.冒险：It is both verb and noun in Chinese.It means do something in spite of jeopardy. as a verb,冒险=take a risk or run a risk as a noun.冒险=adventure ex.没人敢冒险(.verb.)背叛他。(No man would risk to betray him.) ex.我们在听他讲他的冒险(noun.)经历。(We are listening to his adventures .)

风险 is noun .冒险 is verb.

风险评估：evaluate risk 风险报告：risk report 风险分析：risk analysis 风险 is a noun. 冒险：take the risk

these two words are different in structure. 冒险 is 冒(verb) plus 险(noun). it can mean "take a risk to do something", or the behaviour of taking risks, in other words adventures. 风险 is just a noun. it means risk. actually you can say 冒风险 as well: -做这件事他 冒 着很大的 风险。 -He is taking serious risks to do this.

mao4xian3 is a verb feng1 xian3 is a noun