Subdomain VS Subdirectories Impact on SEO

Hi all,

Let's say I have a domain: beautyf*cial.com and I would like to target different regions such as the UK, Singapore, and Taiwan.
Should i create subdomains or subdirectories for example:

UK: uk.beautyf*cial.com
Singapore: sg.beautyf*cial.com
Taiwan: tw.beautyf*cial.com

There are a few queries that I would need help:
1. What is the impact on SEO?
2. will it affect all the regions if my main domain: beautyf*cial.com is down?

Or would you advise me to use subdirectories instead? example:
UK: beautyf*cial.com/en/
Singapore: beautyf*cial.com/en_sg/
Taiwan: beautyf*cial.com/zh_tw/

mystique_blue said:

Or would you advise me to use subdirectories instead? example:

Click to expand...

Subdirectories.