单项选择题
A.To pay extra money. B.To carry it themselves. C.To ask for special permit. D.To drop the excessive item.
A.you can read an ebook on a laptop when you travel B.you can order an ebook using the Ebook Reader C.the ebooks ordered have to be shipped to you D.it takes a lot of trouble reading an ebook
A.One piece. B.Two pieces. C.Three pieces. D.Four pieces.