How can four 4's make 20?

Problem: 4 ? 4 ? 4 ? 4 = 20
In the places of ? you can use any arithmetic operations like +, -, *, / .
But the answer must be 20.

Solution: Not just 20, here is a set of solutions to achieve results between 0 & 20:

0 = [(4 + 4) - (4 + 4)]
1 = [(4 + 4) / (4 + 4)]
2 = [(4 x 4 ) / (4 + 4)]
3 = [(4 + 4 + 4) / 4]
4 = [4 + 4 - √4 - √4]
5 = [√4 + √4 + {4/4}]
6 = [4 + √4 + 4 - 4]
7 = [4 x √4 - {4/4}]
8 = [4 + 4 + 4 - 4]
9 = [4 + 4 + {4/4}]
10 = [44-4 %4
12 = [{4 x 4} - √4 - √4]
13 = [4! / {√4 + (4/4)}]
14 = [4 + 4 + 4 + √4]
15 = [{4 x 4} - {4/4}]
16 = [{4 x 4} + 4 - 4]
17 = [{4 x 4} + {4/4}]
18 = [{4 x 4} + 4 - √4]
19 = [4! - 4 - {4/4}]
20 = [{4 x 4} + √4 + √4]