The urge to go abroad for further study is strong, but it was not until last summer ________ I knew how powerful it could be.
Mom used only half of the money, the rest of which ______ saved for other purposes.
As he reached _____ back door, Jack saw _____ strange sight.
— Has the homework been finished? — Our teacher asked you .
Looking out of the window, I saw the leaves by the wind and whirled into the air.
By the time the fire-engine arrived, the fire by the inhabitants.