ecko3003

Hi All my question is how to differentiate labeling ethers and "oxy' From my notes, an ether is R-O-R one question was draw ethyl vinyl ether which i got correct (CH3CH2OCH=CH2) now i have a question asking for the reverse; give the systematic name of the structure: CH3CH=CHOCH2CH2CH2CH3 and i thought it was propyl ethene ether but the answer is 1 butoxy 1 propene confused to say the least any help would be appreciated