I am very happy about this finding. It is a page with a lot of information about different subjects. The good thing is that this page have drawing, text and the sound. You can hear the text at the same time you read it. I think is perfect to learn anything and in English.
So I must recomend this web page schoool.co.uk . In this page site you can find a good explanation of the respiratory system. You only have to click in Lesson - Breathing and Respiration and you will get several page about respiration. I suggest from page 1 to 15 to study the respiratory system and also the page 28 and 29 about smoking.
I think is also a good idea to click in Lesson - digestion to go to the digestive system pages and take a look from the page 8 to the 19. After this you will understand very much better the digestive process.
I encourage you all to use this resource. Perhaps you don't understand one word or more but as you can read the words you will be able to look up in the dictionary . I think that most of the times you will be able to guess the meaning according to the context.