it's usual to say '예요', instead of '여요','이여요'... hh '여요'&'이여요' are written expressions..

oh.thank you.i just confuse because there are so many 요 at the end of word

요 is used to show 'basic' respect to the listener, the listener could be older or younger than you.

oh.so even if i don't use it.it will be ok right?i thought that 요 is need to show the polite to elder

theseday we hardly use '여요 '이여요' but '예요'and '이예요' ex) what is it? "이게 뭐예요?" who is it? '누구세요? it's me "나예요"