You can drink 20 bottles of soda! The specific calculation is as follows:

1. 10 yuan bought five bottles of soda, and after drinking, there were five empty bottles and five lids;

2.4 empty bottles were replaced by 2 bottles of soda, and 4 bottle caps were replaced by 1 bottle of soda, leaving 1 empty bottle and 1 bottle cap. After drinking, there are 4 empty bottles and 4 caps;

3.4 empty bottles for 2 bottles of soda and 4 caps for 1 bottle of soda. After drinking, there are 3 empty bottles and 3 caps.

4. Replace 2 empty bottles with 1 bottle of soda. After drinking, there are 2 empty bottles and 4 lids;

5. Replace two empty bottles with 1 bottle of soda, and four lids with 1 bottle of soda. After drinking, there are two empty bottles and two lids;

6. Replace two empty bottles with 1 bottle of soda, and after drinking, there are 1 empty bottles and three lids;

7. Borrow an empty bottle of 1, add your own empty bottle for a soda, and after drinking it, drop the empty bottle, leaving four lids;

8.4 Replace the lid with 1 bottle of soda. After drinking, there are 1 empty bottles and 1 lids. Borrow an empty bottle of 1 for a soda, and return it after drinking it, leaving two lids;

9. Borrow two bottle caps to fill a bottle of soda. There are 1 empty bottle and 1 bottle cap after drinking; Borrow an empty bottle of 1 for a soda, and return it after drinking it, leaving two lids; I returned the two borrowed covers, and there was nothing left.

So * * * has: 5+3+3+1+2+1+1+2+2 = 20.

This problem can be calculated by simple mathematics:

Let's analyze the value composition of a bottle of soda:

A bottle of soda = one drink of water+one empty bottle+one bottle cap (abbreviation: 1 water+1 bottle+1 lid).

So: a bottle of soda = 1 water+1 bottle+1 lid.

According to the meaning of the question: two empty bottles = one soda.

Equivalent to: 2 bottles = 1 water+1 bottle+1 lid.

Eliminate 1 bottle on both sides of the equation and get:

1 bottle = 1 water+1 lid

According to the meaning of the question: four bottle caps = one bottle of soda.

Equivalent to: 4 caps = 1 water+1 bottle+1 cap.

And: 1 bottle = 1 water+1 lid, substitute the above formula.

So: 4 caps = 2 water +2 caps.

Remove the two capital letters on both sides of the equation to get:

2 caps = 2 glasses of water

So: 1 cover = 1 water.

Then: 1 bottle = 1 water+1 lid = 2 water.

A bottle of soda = 1 water+1 bottle+1 lid = 4 water.

To sum up:

A bottle of soda = 4 servings of water = 2 yuan.

1 empty bottle = 2 portions of water = 1 yuan.

1 bottle cap = 1 water = 0.5 yuan,

So 10 yuan, buying 5 bottles of soda is equivalent to buying 20 servings of soda.