Konnichiwa Gumi,

Thank you for your post.

よ is a sentence ending particle which used by the speaker to express a strong conviction about something or to emphatically declare something.For example, there is a notable difference between the following sentences,

1)今年、僕(は)花火(を)見なかった。 - I didn't see any fireworks this year...

2)今年、僕(は)花火(を)見なかったよ。- I didn't see ANY fireworks this year!!

Check out this grammar point too: https://www.japanesepod101.com/learningcenter/reference/grammar/262?

Cheers,

Sono

Team JapanesePod101.com

Hi,

just a little doubt , what is the use of yo よ in this sentence

I have seen it finishing many other informal sentences through the course.

今年、僕(は)花火(を)見なかったよ。