Oh, there is someone knocking at the door. — __________ must be your neighbour, Mrs Black.

Two ______ trees have been planted along the lake since 1998.

Tony is twelve old, but his sister is only one old.

__________ he paint?—Yes, he can. He can do it very well.

Is Mrs.Smith in?—I’m afraid she isn’t．Would you like to ________ a message?