Lawrence Craven, a doctor from the USA, is the author of several published reports, one of ________ introduced the idea in 1953 _________ aspirin could reduce the risk of heart attacks.
It is believed that this book is _______ worth reading than that one.
Mark has _____ good command of English. Therefore, he plays _____very important part in our team.
--- Shall we go out for dinner tonight? --- _________.
--Remember____ we met, John? ----Of course I do. You___ an English novel in the library.
On the top of the hill_____, _____ the old man once lived.