Respiratory system

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Across
  1. 2. When we ............, oxygen goes into our body.
  2. 5. The air will go through ..... to our lungs
  3. 7. The air will enter our body.through ...... first.
Down
  1. 1. When we breathe out, our lungs become.....
  2. 3. When we ............, carbon dioxide goes out of our body.
  3. 4. When we breathe in, our lungs become.....
  4. 6. The respiratory consists of nose, windpipe and two ....