The meaning of し

Question

I didn't understand し after 買った

旅行の計画は終わった？
うん、切符を買ったし、ホテルの予約もしてある。

Answer 1

し is used to emphatically add information to a statement, implying that something is among other things(that may be not mentioned as well). The simple formula is as follows:

• Verbs: Informal termination + し
• i-Adjs: i-Adj+し:　美味しい → 美味しいし.
• na-Adjs/nouns: na-Adj/noun + だし:　静か → 静かだし

e.g. その喫茶店は料理が美味しいし、値段がひくいし、それに駐車場があるし。 　　　　
The food on that restaurant is delicious(among the next facts), also the prices are low, and what's more, they also have parking.

We can see the emphatically adding of information here with the rough translations for し.

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This し pattern is normally written or spoken with more than 1 し on the sentence, however, you can have only one し on the sentences and end with it (although is sometimes not seen as correct).

おいトムくん、もう彼女ができたの？ - Hey Tom, have you gotten yourself a girl already?

彼女？！時間がないし… Girlfriend?! I don't have time for that(among other reasons).

Answer 2

This し is an emphatic 'and'.

切符を買ったし、ホテルの予約もしてある。
I bought a ticket and what's more the hotel's been booked.