YOU SAID:

Opportunity did not knock until I built a door.

INTO JAPANESE

私がドアを建てるまで、機会はノックしませんでした。

BACK INTO ENGLISH

I didn't knock on the opportunity until I built the door.

INTO JAPANESE

私はドアを建てるまで機会をノックしませんでした。

BACK INTO ENGLISH

I didn't knock on the opportunity until I built the door.