twos
next sentence is one of subtitles in TED Talks.
which is why you get the terrible twos.
I can't understand the last word 'twos' why 's' attached and what are spared.
which is why you get the terrible two.
which is why you get the terrible two-year-olds.
which is why you get the terrible two-year-old.
please teach me.
:Why you feel what you feel | Alan Watkins | timing = 3:23.
https://youtu.be/h-rRgpPbR5w?t=203
回答
“Terrible twos” is a term. Many parents use this term referring to difficulties they experience when their children are two years old. There is always an “s” at the end.
This “s” may be indicating plurality of the behavioral changes of two-year-old children, enormous challenges for the parents, or both. However, “terrible twos” is a term. It is like a name. We just say “terrible twos.” The reason for the “s” is not important.
I'm sorry I've found this sentence on the web. I'm in the feeling I've felt like understood, but any comment I'd appreciate.
:What Are the Terrible Twos? - Verywell Family
https://www.verywellfamily.com/terrible-twos-and-your-toddler-2634394
:Terrible twos: Why are 2-year-olds so difficult? - Mayo Clinic
https://www.mayoclinic.org/healthy-lifestyle/infant-and-toddler-health/expert-answers/terrible-twos/faq-20058314