1. I didn't knwon anyone in my room.
2. I knew no one in my room.
3. I knew nobody in my room.
4. I didn't know all the students in my room.
5. I didn't know all the classmates in my room.
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If "I" is a student, do all the sentences mean the same?
I don't want to guess for you but I'm assuming that they should all make sense and mean the same? Maybe u can try substituting "I" for a name like John or something and then see if the sentences make sense? Hope this helps :)
1. I didn't know anyone in my room.
2. I knew no one in my room.
3. I knew nobody in my room.
4. I didn't know all the students in my room.
5. I didn't know all the classmates in my room.
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All sentences are grammatical. #1,2,and 3 are the same. #4 and #5 are different from the other sentences. I knew some of the students in the room. I didn't know the other students in the room.
All your sentences in the second set are correct. And, yes, the meaning shifted a bit in the last two. =)
Yes, all of the sentences convey the same meaning. They all indicate that the speaker had no familiarity or acquaintance with anyone present in their room. However, the phrasing and word choice may vary slightly in each sentence.
1. "I didn't know anyone in my room" - This means that there were people in the room, but the speaker did not know any of them.
2. "I knew no one in my room" - This has the same meaning as the first sentence, stating that there was nobody in the room whom the speaker knew.
3. "I knew nobody in my room" - Again, this expresses that there was no person in the room whom the speaker had any familiarity with.
4. "I didn't know all the students in my room" - This specifies that there were students present, but the speaker did not know all of them. However, there may have been some students they did know.
5. "I didn't know all the classmates in my room" - Similarly to the previous sentence, it implies that the people in the room were classmates of the speaker, but the speaker did not know all of them. It leaves open the possibility that they knew some of the classmates.