Ответ:
1. Are the accents different in the north and south of England? Yes, they are
.
2. Is your teacher in your classroom? Yes, he is.
3. Are you and your classmates university students? Yes, we are.
4. Are you from Russia? Yes, I am.
5. Is your mother Italian? Yes, she is.
6. Is Japanese a difficult language? Yes, it is.
А сейчас грамматика
Здесь мы видим глагол 'to be' (а точнее, его формы - am, are, is). В зависимости от лица, ставим одну из этих форм.
Am + I
Are + you, we, they
Is + he, she, it
О кратких ответах
В зависимости от лица, ставим или is, или am, или are.
Yes, + I/you, we, they/he, she, it + am/are/is .