They（）the book all the morning.

A:are reading B:have read C:had read D:have been reading

若在工作簿Book2的当前工作表中，引用工作簿Book1中Sheet1中的A2单元格数据，正确的引用是（）。

A:[Book1.xls]!sheetA2 B:Sheet1A2 C:[Book1.xls]sheet1!A2 D:sheet1!A2

The book is worth（　）

A:read B:being read C:reading D:having read

This book costs ______ that one.

A:twice more B:twice more as C:two times more as D:twice as much as

This book ______ me twenty dollars.

A:is cost B:was cost C:cost D:have been cost

The book ______ with the development Of Information Technology.

A:copes B:deals C:settles D:comes

This book (embraces) many subjects.

A:adopts B:covers C:presses D:accepts

Is it necessary （） the book immediately.

A:for him to return B:that he returns C:his returning D:to him return

"The parent book is______．

A:the Sailing Directions B:the Corrections to Sailing Directions in force C:The Annual Summary of Notice to Mariners D:The Weekly Edition"