He（ ）four lectures on modern philosophy, but he only gave two because of his illness.
A.
would give
B.
had given
C.
should have given
D.
must have given
正确答案是C
He（ ）four lectures on modern philosophy, but he only gave two because of his illness.
He（ ）four lectures on modern philosophy, but he only gave two because of his illness.
A.
would give
B.
had given
C.
should have given
D.
must have given
正确答案是C