根据句意,用所给动词的适当形式填空。 When I saw the parade in Disneyland, I couldn’t stop ___________ (take) photos . It takes about three hours ___________ ( fly )to Hong Kong . Students should read more books ___________ ( improve ) their writing . Sadly, the little dog ___________ (die) for some time . You must ___________ (return) these books to the library as soon as possible.