It’s 21 past 4 (Official clock system).

04:21

It’s 21 past 4.

Correct answer

04:22

It’s 22 past 4.

Error: 1 minute later

04:05

It’s 5 past 4.

Error: read minutes starting from hour markings and adding minutes

04:20

It’s 20 past 4.

Error: confuse hour and minute hands