We have received your letter of September
问题:
We have received your letter of September 12,()we are glad to know that you are interested in our electric heaters.
A.which
B.atwhich
C.fromwhich
D.inwhich
We have received your letter of September 12,()we are glad to know that you are interested in our electric heaters.
A.which
B.atwhich
C.fromwhich
D.inwhich