隆隆

lónglóng

隆隆 — lónglóng

1. to rumble; (sound) rolling and deep, as thunder or heavy machinery

   雷声隆隆，雨点开始打下来。 léishēng lónglóng yǔdiǎn kāishǐ dǎ xiàlái — The thunder rumbled, and the raindrops began to fall.