3 sentences

1. 他们多年后重逢，旧情复燃。

   tā​men duō nián hòu chóng​féng, jiù​qíng fù rán.

   They met again after many years, and their old flame was rekindled.

   Source: Dong Chinese Dictionary

2. 希望的火焰在他心中燃着。

   xī​wàng de huǒ​yàn zài tā xīn​zhōng rán zhe.

   The flame of hope is burning in his heart.

   Source: Dong Chinese Dictionary

3. 这种气体极易燃，请远离火源。

   zhè zhǒng qì​tǐ jí yì rán, qǐng yuǎn​lí huǒ yuán.

   This gas is highly flammable; please keep it away from ignition sources.

   Source: Dong Chinese Dictionary