2.
A: How long
? (you, be, waiting)
B: I
for 30 minutes. (be, waiting)
A: How long
have
you
been
waiting
? (you, be, waiting)
B: I
have
been
waiting
for 30 minutes. (be, waiting)
A: ¾ó¸¶³ª ¿À·§µ¿¾È ±â´Ù¸®°í ÀÖ´Â ÁßÀÌ´Ï?
B: 30ºÐ° ±â´Ù¸®°í ÀÖ¾î.