2 sentences

1. 游客不得擅自跨越国境。

   yóu​kè bù dé shàn​zì kuà​yuè guó jìng.

   Tourists are not allowed to cross the national border without authorization.

   Source: Dong Chinese Dictionary

2. 这场跨越国境的拉力赛吸引了来自世界各地的顶尖车手。

   zhè chǎng kuà​yuè guó​jìng de lā​lì​sài xī​yǐn le lái​zì shì​jiè gè dì de dǐng​jiān chē​shǒu.

   This cross-border rally attracted top drivers from all over the world.

   Source: Dong Chinese Dictionary