long in the tooth
Debra was a bit long in the tooth to continue her career as a professional dancer so she became a teacher.
After realising he was long in the tooth, John was a bit too long in the tooth to continue his job, john retired.
The music industry is a young persons industry; many popular singers from the 90's are already a bit long in the tooth.
Meaning: A person who is long in the tooth is a bit too old to do something.
Etymology: from the practice of examining the length of horses' teeth when estimating their age
Get the Axe
Bill got the axe for stealing office supplies.
Sarah got the axe for being late to work.
Tina got the axe after making offensive comments towards her co-worker.
Meaning: If someone gets the axe, they lose their job.
Etymology: Derived from people getting beheaded, loosing your job is the equivalent of loosing your life.
silver surfer
After seeing ben's dad buying stuff on taobao I realised he was a silver surfer.
Jenny's grandmother keeps up to date by watching youku, she is a silver surfer.
Ted's granddad uses qq more than he does the telephone, he is a silver surfer/
Meaning: A silver surfer is an elderly person who uses the Internet.
Etymology: Silver refers to grey hair and surfer refers to someone who surfs the internet.