YOU SAID:

i should have a large egg

INTO JAPANESE

私は大きな卵を持っているべきです

BACK INTO ENGLISH

I should have a large egg

INTO JAPANESE

私は大きな卵を持っているはずです

BACK INTO ENGLISH

I'm supposed to have a big egg.

INTO JAPANESE

私は大きな卵を持つことになっています。

BACK INTO ENGLISH

I'm supposed to have a big egg.