单项选择题
A．an advertisement of an airline B．a notice for airline passengers C．a schedule of an international flight D．an introduction to an airline company
A．An ebook is ordered in the same way as a print book is. B．The size of the words in an ebook cannot be changed. C．The downloading time is decided by the ebook’s size. D．There is less fun reading an ebook than a print book.
A．To pay extra money. B．To carry it themselves. C．To ask for special permit. D．To drop the excessive item.