they的三种形式

They are going to move to a new house next week.

下星期他们将迁入新居。

I have a dog and a cat， but they fight all the time.

我养了一只猫和一只狗，但它们老是打架。

They have maintained their optimism in the face of desolating subjugation.

面对遭征服的悲惨命运，他们保持了乐观的态度。

They found a labyrinth of tunnels under the ground.

他们发现了一处迷宫似的地道。