Learn French: Je pars en vacances avec mon bagage. - I am leaving on vacation with my luggage.

The verb partir (to leave) is an irregular -ir verb. Instead of keeping the 't' and adding typical endings, you drop the '-tir' and add '-s' for je and tu, giving us je pars.

Why is vacances plural when the English translation says singular 'vacation'?

In French, the word for vacation or holidays is almost always plural: les vacances. You will rarely see it in the singular form, so 'on vacation' is always written as en vacances.

Why do we use the word en for 'on' in this sentence?

Prepositions rarely translate word-for-word. While English says 'on vacation', French uses the set expression en vacances. You cannot use sur (on) in this context.

Is bagage singular or plural here, and why does it use mon?

The word bagage is a masculine singular noun meaning a single piece of luggage, which is why it uses the masculine 'my' (mon). To talk about your luggage as a collection of bags, you can use the plural mes bagages.