1. His haphazard reading left him unacquainted with the authors of the books.
    他信手翻阅各种书籍, 因此对这些书的作者一无所知。

2. Here a haphazard method of teaching; there the whole task laid out in a system.
    一边采用的是无计划无系统的教学方法；另一边则是有系统地施教。