I called ________ his house, but he wasn't in. So I left a message telling him I would call ________ him the next day.
[ ]
|
A.on; on |
B.at; at |
|
C.at; on |
D.on; at |
How about two of you ________ trees?
[ ]
|
A.plant |
B.to plant |
|
C.planted |
D.planting |