来た2日後に vs 来て2日後に vs 来てから2日後に


> 日本に **来た2日後に** この本を買った。  
>  日本に **来て2日後に** この本を買った。  
>  日本に **来てから2日後に** この本を買った。

I created these sentences from similar-looking examples I found on Google. Are
they all grammatical? These all mean "I bought this book two days after I came
to Japan," correct? What is the difference between them?




They do all mean generally the same thing, but as always examining the
difference can be revealing.

日本に来 **た** 2日後にこの本を買った is structured like (日本に来た2日後)にこの本を買った. 日本に来 **て**
2日後にこの本を買った can be parsed the same, but it can be also parsed as
日本に来て(2日後にこの本を買った). This difference becomes more visible when you remove 2日後に:

  * 日本に来たこの本を買った (I bought this book that came to Japan)
  * 日本に来てこの本を買った (I came to Japan and bought this book)

来てから is 来て+から and the extra から emphasizes the ordering or causal effect. The
speaker really wants to communicate that the purchase of the book happened
after he came to Japan, and presumably the context demands that emphasis, for
example someone said the book was really popular back in the US.

