重点讲解：
1. at the same time
同时；
eg. Different things are happening in these two worlds at the same time.
两个不同的世界却在同一时刻发生著不同的事。
eg. It was busy and crowded and yet at the same time peaceful. This was a paradox she discovered over and over again . . .
这里繁忙而拥挤，但同时又很安静，这是她一再发现的一种矛盾现象。
2. at work
干活儿；做工作；忙着做事；
eg. He is currently at work on a novel.
他这会儿正忙着写一篇小说。
eg. Television cameras were invited in to film him at work.
电视台摄像师被请进来拍摄他工作的镜头。
3. fresh air
户外空气；（尤指未受污染的）新鲜空气；
eg. 'Let's take the baby outside,' I suggested. 'We all need some fresh air.'
“我们带宝宝出去走走吧，”我提议。“我们都需要呼吸一些新鲜空气。”
eg. I hope you can enjoy the fresh air and great views here.
我希望您可以享受这里的清新空气和宜人风景。
