marcar la opcion correcta:
1) i be/am/is twelve years old
2) they be/am/are in the garden
3) it am/is/are six o'clock
4) you be/is are a dentist
5) i am/is/are in the station
6) it am/is/are very hot
7) my sister am/is/are at work
8) i be/am/are hungry
9) we am/is/are students
10) the book be/is/are. about tigers​