How to control 2 lamps (bulbs) in parallel and 2 lamps in series by switches English video tutorial

Hi every one, as you know that we published a post in last class about controlling 4 lamps (bulbs) by 4 switches . In today callas we will control the 4 lamps again but 2 in parallel and 2 in series. Last class we used 4 one way switch for controlling 4 lamps but in this class we use only 3 switch because we will control 2 lamp in series.
As we know that in parallel circuit voltage are same and and current (Amp) is different, in last class we controlled 4 lamps by 4 switch in parallel and we have voltage(V) are same in and current are different (Amp).
But in this class we will control only 2 lamps in parallel, so in parallel controlled lamps have voltage are same and current is different and in series controlled lamps voltage are different and current is same.
So lets come to the point, when we have a parallel circuit then we have voltage(V) are same and current (Amp) in different. And when we have a series circuit then we have voltage are different and current is same.

Coming to controlling 2 lamps in parallel and 2 in series by 3 switches.
Requirements :
4 lamps (bulbs) 100 to 200 watts
3 one way switches
11 pieces of electric cable
AC supply 220 to 230 volts

Connect all things as shown in below figure.

4 lamps controlling

So here is an video tutorial from which you can learn about the today class, so for better understanding kindly watch the below video tutorial.
Note that the video tutorial is in an English language.

Having watch the video tutorial i hope you will be  understood and if you have any question regarding this class then do ask me in comments section below.