"That is my biggest pumpkin."

Translation: Itu adalah labu terbesar saya.

[donny309620]

I think you could also say "Itu adalah labu saya yang terbesar".

[nickmati]

Agreed. "Ini adalah gaun saya yang terkecil" was given as the correct answer to a previous exercise. I don't see why it would be wrong here.

[Fitzroy1911]

1) why is "Itu labu terbesar saya" not accepted?
2) why is "Itu adalah labu saya terbesar" not accepted?

[DanPaz3]

"paling besar" vs "terbesar" ?

[Diponegoro57]

They are the same and interchangeable, so far as I know.