Some questions to plate tectonics

 

I woukd like seismologist in general and USGS in perticular to answer following questions
1) Why major quakes occurs at places other than plate boundaries. ( fault line is not correct answer as there can not be relative movement inside a  big plate)
2) why several major quakes on various plates ,not related to each other ,on a given date?
3) why deep quakes ? ( Subduction plate reaching 800 km depth without melting is not possible)
4) Why small quakes daily on same plate /locations
5) why ,sometimes aftershocks are bigger than main quakes?
6) Why often major quakes are accompanied by heavy rain
7) Why ,generally, major quakes occur at locations where Moon /Sun are at Zenith/Nadir or Rising Seiitng?