Four goodness' sake

Use 4 four times with simple operations so that you get the answer 12. Can you make 15, 16 and 17 too?

Problem

 

Write down the number $4$ four times, putting operation symbols between each $4$ to make a calculation.

For example, you could write $4 \times 4 \times 4 - 4 = 60$

Which symbols could you choose to make the answer $12$?

What about if you wanted the answer to be $15$? Or $16$ or $17$?

Once you've tried that, see if you can make every answer from $0$ to $10$. And once you've tried that, see if you can go all the way up to $20$!