重点讲解：
1. at first 最初；起初；开始时；
例句：At first, he seemed surprised by my questions.
起初，他似乎对我的问题感到惊讶x^GOlok+@!!fnJ。
2. go by （时间）流逝，过去；
例句：My grandmother was becoming more and more sad and frail as the years went by.
随着时间的流逝，我的祖母变得日益伤感和虚弱tk@2[[#Z8f。
3. look back 追忆；回顾；
例句：She can look back on her career with great satisfaction.
她回顾自己的经历觉得心满意足yVz]=&HyiN2。
4. as a whole 整体而言；总体上；
例句：As a whole, this article is well written.
总的说来，这篇文章写得很好&&tej;74fLOkCTjxQ。
5. keep up with 跟上（活儿、人等）；同…做（或理解）得一样好；
例句：He made an arduous effort to keep up with the rest of the class.
他努力跟上班上其他同学2z-Zh7,s1wE。