Fireworks are things that explode in the sky to make a light of different colours. They are usually very noisy, but extremely beautiful. Fireworks are used to celebrate big occasions, for example, at New Year’s Eve or at a wedding.
You can use the verb: to light, or the phrasal verb: to set off with the noun fireworks. For example: on New Year’s Eve I set off lots of fireworks to celebrate the start of a new year.