I think you all know what oxygen is, but if you don't it is what humans and animals breath.
After the plant has all three things, it has completed the process of photosynthesis, at least it's first process of it.
The second step of photosynthesis is when plants take in carbon dioxide.
According to NASA, of all the sunlight that reaches earth, only about 48 percent of it hits the surface and only a portion of that is captured through photosynthesis. The rest is reflected back by earth’s atmosphere or absorbed by the atmosphere.
Steps of Photosynthesis? | Yahoo Answers
Only plants can photosynthesize, but both plants and animals depend on respiration to release the chemical potential energy originally captured through photosynthesis.