How to Say "It was my younger brother's birthday last week." in Korean?

"It was my younger brother's birthday last week." in Korean is 지난주에 동생 생일이었어요. (jinanjue dongsaeng saengirieosseoyo)

케이크 만들어요. (keikeu mandeureoyo) - I make a cake.
케이크 만들고 있어요. (keikeu mandeulgo isseoyo) - I'm making a cake.
지금 뭐 만들고 있어요? (jigeum mwo mandeulgo isseoyo) - What are you making now?
딸기 (ttalgi) - Strawberry
딸기 케이크 (ttalgi keikeu) - Strawberry Cake
딸기 케이크 만들고 있어요. (ttalgi keikeu mandeulgo isseoyo) - I'm making a strawberry cake.
구월 (guwol) - September
엄마 생일 (eomma saengil) - Mom's Birthday