A few quick corrections: It's not completely incorrect to say "a firework" but it is much more common to refer to them as "fireworks" (plural). The fireworks were shot off into the dark sky and radiated for a few seconds Is correct. I hope this is helpful!

Hello, Ethan. I would make a couple of corrections. Please remember to use the correct tense in your sentence. It would sound the most natural to say, " The fireworks were shot off into the dark and radiated for a few seconds." I have used the past tense for the words "shoot" and radiate". Also, as Kimberly mentioned, it is more common to say the plural form of firework, "fireworks." (Chances are you will be shooting multiple fireworks off at once, so we use the plural form.) Otherwise, good job!

In British English we would say "the fireworks shoot off into the and sky radiated for a few seconds" Were is obvious and redundant so in daily speak we omit it. It is obvious someone had to light them and they shot of into the sky. They were ignited by somebody, either manually or electronically.