Lego
Refers to the Lego brand and its products, especially the plastic building blocks. Used as a noun in Japanese.
子供の頃、レゴでよく遊んだ。
When I was a child, I often played with Lego.
The kids love playing with Lego.
説明書を見ながらレゴを組み立てた。
I assembled the Lego set while looking at the instructions.