a. As his father played chess, so did he. b. Just as his father played chess, so did he. Do these mean 1. His father played chess and so did he. 2. He played chess in the same way his father played chess. 3. He played chess because his father did. 4. He played chess at the same as his father did. The sentences are mine. I had asked a similar question yesterday, but the structure of the sentences is not the same. I think (b) means (1) and (b) means (3). Many thanks.