That is one of those books that ____ worth reading.
____ he told us is the news ____ China has got 32 gold medals in the Athens Olympic Games, ____, of course, made us feel very excited.
Rarely ________ such a silly thing.
Prices of food in that area ____ sharply since word came that the war would break out soon.
Rather than ____ on a crowded bus, he always prefers _____ a bicycle.
______ Marx's works with Engels', and you'll find many differences.