Luna posted a photo with a caption that read, "8th Anniversary already...let's light up the night!"

While Amber posted three photos and a longer caption that read, "Found a lot of good memories going through old photos^^

When I didn't know how to say anything, they helped me, when I was scared and discouraged they told me not to stop and to never give up, when I was lonely they would pick up my random phone calls, and they even laughed at my stupid dad jokes haha… its been a crazy but amazing 9 years with them, laughing together, crying together, and even arguing with one another… and I hope to make more special memories with these crazy girls :) Thank you to my members, always! Love you guys!

f(x) is 8 years old!! Just want to thank all you MeUs out there. If theres no MeU, theres no f(x)! I can still hear all those crazy fan chants like it was yesterday. Thank you guys for everything and we going to keep working hard! Love you guys, THANK YOU! [sic]"

SEE ALSO: Krystal's past letter to late f(x) member Sulli goes viral

Seeing this, fans commented, "Thanks for all these years, I'm so proud of you," "Happy 8th anniversary," "Love you and miss you," "Waiting for your comeback, happy anniversary," "Congratulations!"

• ?? 8?... ??? ???? ! ??? ??? ?? ??

A post shared by Luna ?? (@hermosavidaluna) on Sep 5, 2017 at 12:01am PDT

??? ????? ?? ???? ????^^ ?? ?? ? ??? ? ? ? ?? ????, ?? ??? ??? ????? ?? ???, ??? ??????? ????? ??, ?? ???? ?? ?? ? ?? ??, ? ?? ?? ????? ??????.. 9??? ?? ?? ?? ???….??? ??? ????? ???? ? ?? ?????! ?? ??? ?? ??? ???! ????? ?? 8??? ?? ?? ???? ?????!!! ???? ???? ????? ??????! ??? ?? ??? ????? ?????? ? ????. ?? ??? ?????^^ ???? ????! Found a lot of good memories going through old photos^^ When I didn't know how to say anything, they helped me, when I was scared and discouraged they told me not to stop and to never give up, when I was lonely they would pick up my random phone calls, and they even laughed at my stupid dad jokes haha… its been a crazy but amazing 9 years with them, laughing together, crying together, and even arguing with one another… and I hope to make more special memories with these crazy girls :) Thank you to my members, always! Love you guys! f(x) is 8 years old!! Just want to thank all you MeUs out there. If theres no MeU, theres no f(x)! I can still hear all those crazy fan chants like it was yesterday. Thank you guys for everything and we going to keep working hard! Love you guys, THANK YOU!

A post shared by Amber J. Liu ??? (@ajol_llama) on Sep 4, 2017 at 11:04pm PDT