busy的反义词是free。
“busy”的中英文对照例句：
He is busy with some important work.
他正忙于处理一些重要的事情。
He was busy getting ready for his journey.
他正忙于准备旅行。
The shop looked out into a busy street.
这商店濒临近一条繁忙的街道。
The traffic was at its height at the busy junction.
在繁忙的交叉路口，车辆来往正处于高峰。
I tried to call Mr. Cooper, but the line was busy.
我想给库柏先生打个电话，但一直占线。
To forget his trouble, he busied himself in his garden .
为了把烦恼忘却，他让自己忙于花园的工作。
As the final examinations draw near, students begin to busy themselves with reviewing.
当期末考试即将来临时，同学们开始忙于复习。
I tried to reach him, but the line was busy.
我试图和他联系，但他的电话占线。
The Strand is one of London's busiest and most affluent streets.
斯特兰德街是伦敦最繁华、最富足的街道之一。
He busied himself with the camera.
他忙着摆弄那个相机。