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Left: The "worms" are big mosquito larvae. For breathing they have a snorkel at their end.
2. photo: Some of the larvae have changed into a new "dot" which is called a pupa.
It has two horns at the front for breathing.
3. photo: Some of the dots have also changed: Mosquito fathers have come out of the water.
They do not have a sting. So they cannot suck blood
Right: The kindergarten lady tells the children what has happened.