1
Christian was singing in the classroom.
2
Christian will be singing in the classroom.
3
Christian was singing in the classroom.
4
Christian has sung in the classroom.
5
By the end of the period, Christian will have sung in the classroom.
6
Before he came to school, Christian had sung in his house.
7
Christian sings in the classroom.
8
Christian will sing in the classroom.
9
Christian sang in the classroom.
