Both .... and, not only...but also, either ..or, neither...nor, as well as are called co-ordinating conjunctions. They are used with a noun, adjectives.Both the forms must be parallel.
For example: Raj can play both cricket and football very well. Here , after 'both' cricket is used. So , after and football is used.
Raj is not only kind but also helpful . Here, after 'not only' the adjective kind is used and after 'but also' the adjective'helpful; is used.
Incorrect: Raj can play both cricket and also dances well.
Raj is not only kind but also helps others.
Either ... or: This denotes preference for one thing or a person.
For example : There are two ways to solve the problem. Choose either the first one or the second one.
Neither .... nor .. It means both are not preferred. For example: Neither Raj nor his friend plays football (both of them don't play football)
Important point to note: You can use a singular or plural noun or a pronoun after ' or' or 'nor' However, when you use a plural after- or/nor - you should use the plural form. The form you use after 'either'/neither doesn't count.
Let me exemplify it more: Neither Raj nor his friends play football.
You can take help either from the teacher or the counselors regarding the rules.
In the above examples , you will observe that when the plural noun- friends - is used the verb changes to play. When -nor- is followed by - friend -the verb takes 's' and becomes -plays.
As well as:Mary cooks continental as well as intercontinental food very well.
She speaks fluently as well as convincingly.
Rani is not only smart but also intelligent.
Both Raj and Ravi speak English fluently.
Neither the captain nor his team has arrived.
Neither the captain nor his friends have called us.
Either the green book or the red book has the necessary information.
Either the captain or the members of the team know the exact number of the seats available.
Raj is smart as well as handsome.
Mary plays the Guitar as well as the trumpet.