[tóng shí]
[副]
（同一个时间） at the same time; simultaneously; concurrently; in the meantime; meanwhile; in the interim; per interim
exist simultaneously; exist side by side
同时存在
happened at the same time; coincide; concur; synchronism
同时发生
[连]
（并且） moreover; besides; furthermore
The task is arduous; besides, there's not much time.
任务艰巨，同时时间又很紧迫。