為更專門的工作for more specialized work
為晉升的前途for prospects of promotion
為更高層次的工作責任for higher responsibility
為擴大工作經驗for wider experience
找一份更好的工作to seek a better job
由於雇用期滿due to expiry of employment
找到了更好的工作sought a better job
由於公司倒閉due to close-down of company