这里的a是什么s ?
母语人士的回答
Rebecca
在这里, a s手段while, during (在同一时间)。换句话说,他们的意思flock to transithubs在上下班时flock to transithubs 。例子: She came into the kitchen as I was cooking dinner. (我正在做晚饭,她进了厨房。)例子: I wrapped the presents as I watched the news. (我在看新闻时包裹了礼物。)