The river______ surface used to be covered with waste and rubbish is now taking on a new look.
--- Is this book familiar ______ you? --- Sure. I am also familiar ______ its writer.
The place _______ I visited last summer is just the place _______ I spent my childhood.
The machine has ______ again; I think we’d better buy a new one.
Recently I have bought an iPad on the website of taobao.com, _______ the price is very reasonable.
When he knew that he had passed the driving test, he smiled _______.