''' When should you choose between the HARMONY and the MELODY ,what part is more difficult to achieve (or to sing)?"

Harmony

Explanation:

Melody is the main part of the song, so you are the most familar with it. Medody is not the main part of a song, so you have to work harder to sing it.

like any other technology, art form or field, digital cameras have their own nomenclature. the alphabet soup of jargon can be as confusing and intimidating as trying to understand how all those dials, buttons, levers and menu options affect the pictures and videos that you capture. fear not, because we've defined the most important words, phrases, commands and options you'll need to know when shopping for and learning to operate your new dslr, mirrorless, smartphone or other camera.