improve phrasing

en/01.1.md

@@ -15,15 +15,18 @@ There are many ways to configure the Go development environment on your computer
 In case you want to install more than one version of Go on a computer, you should take a look at a tool called [GVM](https://github.com/moovweb/gvm). It is the best tool I've seen so far for accomplishing this task, otherwise you'd have to deal with it yourself.
 
 ## Install from source code
-Go 1.5 completely remove the C code，Runtime、Compiler、Linker powered by Go,Achieve bootstrapping,You only need the previous version to compile go.
 
-But before Go 1.5 some parts of Go are written in Plan 9 C and AT&T assembler, you have to install a C compiler before taking the next step.
+To compile Go 1.5 and upwards, you only need the previous version of Go, as Go has achieved bootstrapping. You only need Go to compile Go.
+
+To compile Go 1.4 downwards, you will need a C compiler as some parts of Go are still written in Plan 9 C and AT&T assembler.
 
 On a Mac, if you have installed Xcode, you already have the compiler.
 
 On Unix-like systems, you need to install gcc or a similar compiler. For example, using the package manager apt-get (included with Ubuntu), one can install the required compilers as follows:
 
- `sudo apt-get install gcc libc6-dev`
+```sh
+sudo apt-get install gcc libc6-dev
+```
 
 On Windows, you need to install MinGW in order to install gcc. Don't forget to configure your environment variables after the installation has completed.( ***Everything that looks like this means it's commented by a translator: If you are using 64-bit Windows, you should install the 64-bit version of MinGW*** )