tiān / qì / tài / rè / le / wǒ / zài / tài / yáng / xià / zǒu / le / yí / huìr / jiù / tóu / hūn / nǎo / mèn

天气太热了，我在太阳下走了一会儿就头昏脑闷。

It was so hot that I felt dizzy after walking in the sun for a while.