I haven't finished the work you gave me yesterday.
你昨天给我的工作我还没有做完呢.
I'll have some private things to do. So I can't accept extra work. I'm so sorry about it.
我有些私人事情需要处理.因此我无法接受超额的工作.非常抱歉.
I'm afraid I have no time to do this.
我恐怕没有时间来做这些事情.
I'm afraid I can't complete the task by myself. I need more help.
我恐怕一个人完成不了这项任务.我需要更多帮助.
