If the people ahead of us get the red one first, let's pick another colour.
If they pick the red one before us, let's just choose a different colour.
ーIf the people ahead of us get the red one first, let's pick another colour.
「前の人たちが赤色にしたら、他の色を選ぼうね」
people ahead of us で「私たちの前の人たち」
to pick another colour で「別の色を選ぶ」
ーIf they pick the red one before us, let's just choose a different colour.
「彼らが私たちより先に赤色を選んだら、違う色を選ぼう」
to choose a different colour で「異なる色を選ぼう」
ご参考まで!