how are they used in making glass?
As a glass fibre additive.
Metalloid
 Boron trioxide is used as a glass fibre additive, and is also a component of borosilicate glass, widely used for laboratory glassware and domestic ovenware for its low thermal expansion.
what is the basis of arranging the elements in the modern periodic table Atomic number, electron configuration, and recurring chemical properties. what is the purpose of the table? UNANSWERABLE why is called so? Because of the tabular display of the chemical elements. what sorts of elements can we see in it? Nonmetallic elements such as metalloids,  groups of families of elements and elements having metallic lustre. can you name a few of the first form? Boron, silicon, germanium, arsenic, antimony, and tellurium. where are they commonly applied? Alloying components, biological agents, catalysts and flame retardants. what do they do being the second type? They have medical applications, can be used in insecticides and herbicides, also they have antiseptic, antifungal, and antiviral properties.
wiki:8264398
Metalloid [SEP] Glass formation
The oxides BO, SiO, GeO, AsO, and SbO readily form glasses. TeO forms a glass but this requires a "heroic quench rate" or the addition of an impurity; otherwise the crystalline form results. These compounds are used in chemical, domestic, and industrial glassware and optics. Boron trioxide is used as a glass fibre additive, and is also a component of borosilicate glass, widely used for laboratory glassware and domestic ovenware for its low thermal expansion. Most ordinary glassware is made from silicon dioxide. Germanium dioxide is used as a glass fibre additive, as well as in infrared optical systems. Arsenic trioxide is used in the glass industry as a decolourizing and fining agent (for the removal of bubbles), as is antimony trioxide.