Syntactically, Ruby is quite distinctive and bears little resemblance to other programming languages. It's a little annoying at first, but over time you realize that this was done for a reason, and if everything were different, there would be internal contradictions in Ruby.

The language closest in spirit is Python, and version 3. Next come PHP and Perl, and in general all interpreted dynamic programming languages that are popular in web development.

However, when switching from another language, in any case, you will have to rethink each syntactic construction.