When _______how a statue from distant Greece could have appeared in China, researchers explained that no doubt this was a result of Alexander the Great’s influence.

 Hardly ______ his speech ______ the audience started cheering.

Here ________ with a pair of glasses.

Jane opened the door. There ______ she had never seen before. 

Nelson Mandela is，__________ the greatest man of the 20th century，certainly among the most extraordinary leaders．