Why is glass transparent to visible light and opaque to ultraviolet amd infrared light I was thinking that UL and IL are being absorbed when striking glass which makes no light passing through. need clarification.
 A: Assuming (  thanks  LLlAMnYP for the translation)  UL means the ultraviolet part of the spectrum and IL the infrared part, it is an experimental fact that glass is transparent for visible light which is in between . This can be completely described  within the classical theory which defines the index of   refraction for the degree of transparency. 
What happens when  matter is not transparent to the incident light, as for ultraviolet and infrared for glass , is the same as what happens with all non transparent materials. Light may be reflected, or absorbed in the first few atomic layers. 
One has to go to the quantum mechanical frame to understand the complexity. The atoms, molecules and the lattices composed  out of them respond to specific frequencies in various ways. 
For transparent materials, the photons making up the light do not interact, or interact coherently, with the lattice and molecular states, losing no energy. At most some may  be reflected at the surface . It is a matter of construction of the lattice too ( think diamond and chunk of carbon)  Opaque materials have centers which interact with the incoming photons, absorbing them  and turning the energy to heat, or also reflecting them from the surface in a disorganized fashion. 
When energies of photons are large, like x-rays most materials are transparent because the probability of the photons to interact is small and many go through unscathed.
