When can desu be omitted? Is it needed for every single sentence? Also, can I add sentence ending particles to the end of any word? Such as, "学校ね？" as in "school, right?" Thanks.
Edit: I'm still a bit confused on the topic. To my understanding, you need something that acts like a verb at the end of a sentence like です/だ. I was taught that です wasn't needed after an i-adjective, but was needed after an na-adjective? Is that true, if so, why? Does an I-adjective act like a verb? This also is a bit off topic, but when can you use だ instead of です and when can't you? I've currently been living in Japan for a while now, and I still can't get this basic concept down which is why it's worrying me. I've also read a bit, but still struggle. Thanks for your help!