孩子们在操场上画了一个三角形的图案。

The children drew a ___three-cornered shape on the playground.

这次比赛变成了一场三方角逐，包括我们学校、隔壁学院和当地俱乐部。

The competition became a ___three-cornered contest between our school, the neighboring college, and the local club.