we use many where we can counting . for example we can count numbers of apples, tables​ etc. contary to it we use much where we can not count but measure amount.for example we can know amount of milk but can not count in number

parents mean both mother and father so word parents is plural. right sentence is my parents are smart. if you want to say either mother or father then you use like singular

You should practice daily to speak English with correct pronunciations and take part in debates with friends

Use of either - or if second subject is singular then use it like singular. if second subject is plural then use it like plural. for example- either I or ram is going to jaipur . in this example second subject is singular (ram) either I or you are going to jaipur. in this example second subject plural (you).

definition of sound :- Vibrations that travel through the air or another medium and can be heard when they reach a person's or animal's ear.

I had received.

Sarvarthasiddhi Maurya was name of father of Chandragupta maurya

when there are two alternatives possible, then use of whether. For example- whether you will take a tea or coffee. Here there are two options possible . first is tea and second is coffee.

you should practice to speak words on the daily basis. Besides it you should participate in debates on any topic with your friends it will help you a lot of.

simple mean of county is territory. for example- English county is club .