Question about three sentences:
1a. He betrayed the cause which he was paid to support.
1b. He betrayed the cause to support which he was paid.
1c. He betrayed the cause , to support which he was paid.
2a. He told us the object of his life which he had run such dangerous and undergone such toil to gain.
2b. He told us the object of his life to gain which he had run such dangerous and undergone such toil.
2c. He told us the object of his life, to gain which he had run such dangerous and undergone such toil.
3a. He asked me to be careful about it, which he left the room saying.
3b. He asked me to be careful about it,saying which he left the room.
3c. He asked me to be careful about it saying which he left the room.
Question: Which is/are grammatically correct?
Does each pair of sentences have the same meaning?