According to one statistic , office workers are only productive for 31 per cent of their workday. While most of this lack of productivity is due to external sources like phone usage or outside ...

作为一位常见的理科教师，在备课的时候，数学、化学这些科目的公式在PPT里排版，真是让人头大。为了不让公式格式乱掉，多数老师只能先把公式编辑器里的内容截图，再插到PPT里。这么搞不仅麻烦，还容易让公式变得模糊，而且截图之后想改都改不了。

Most of our time at work involves writing, speaking and presenting – from emails and PowerPoint decks to reporting ... The double helix is like a twisted ladder that untwists and unzips when ...