Sentences 1 and 3 mean the same thing, and 2 and 4 are close.
Sentences 5 and 6 make me wonder -- were you reading and walking at the same time? "While" indicates simultaneous actions.
1. When I entered the room, she was playing the piano.
1-1. When I entered the room, she played the piano.
1-2. As soon as I entered the room, she was playing the piano.
2. While I entered the room, she was playing the piano.
3. I entered the room while she was playing the piano.
4. I was entering the room while she was playing the piaon.
5. I was entering the room while I was reading a book.
6. I entered the room while I read a book.
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Are they all grammatical? Is #2 right?
What are the differences in meaning?
Does #1-1 mean #1-2? What is the meaning of 'while' in #4? Although, or however? Does #5 mean #6? What is the difference between them?
2 answers
1-1. When I entered the room, she played the piano.
1-2. As soon as I entered the room, she was playing the piano.
These sound as if she started to play the piano when you entered the room, not that she was already playing and then you walked into the room.
1-2. As soon as I entered the room, she was playing the piano.
These sound as if she started to play the piano when you entered the room, not that she was already playing and then you walked into the room.