left
had left
has been leaving
None of these
I had finished the book yesterday
I finished the book yesterday
I have finished the book yesterday
I was finishing the book yesterday
to seeing
seeing
to see
to have seen
They are digging the canal for a week
They have been digging the canal for a week
They had dug the canal for a week
They dig the canal for a week
are passed
passed
have passed
had passed
did not have
have not had
are not having
had not had
I am here since Monday
I have been here since monday
I am here from monday
I was here since monday
No sooner
the bell rang
than the teacher entered
the class
freezes
will frieeze
would frieeze
froze
has known
had known
will know
knew