diff --git a/README.md b/README.md
index e328b96..0f2bdbc 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,7 @@
 
 ## Installation
 
-To install `rmv`, run the following command:
+To install `rmv`, [Rust](https://www.rust-lang.org/) needs to be installed. Once Rust is installed, run the following command:
 
 ```sh
 cargo install --git https://git.deadbsd.org/falso/rmv.git
@@ -14,6 +14,8 @@ cargo install --git https://git.deadbsd.org/falso/rmv.git
 
 To use `rmv`, you need to specify the path to the directory where the files to be renamed are located, a regular expression pattern to match against the filenames, and a replacement pattern for the matched filenames.
 
+In the `--replacement` argument, you can use reference groups in the pattern by using `\1`, `\2`, etc. For example, if you have a pattern `"Season (\d) Episode (\d)"`that matches `"Season 1 Episode 2"` and you want to replace it with `"S01E02"`, you can use the following replacement pattern: `"S\1E\2"`.
+
 Here is an example usage:
 
 ```shell