1. OR

A) When you use OR to join two verbs, both verbs should be in the same form; e.g.

INCORRECT: In the morning we used to go for a morning walk or did exercise at home earlier.
CORRECT: In the morning we used to go for a morning walk or do exercise at home earlier.

(GO is V¹, so it will be DO,   not DID).

COMPARE
a) We used to go to the cinema or watch the television.
b) We went to the cinema or watched the television.

B) We use OR (not AND), after the negative form of a verb; e.g.

INCORRECT: There were no books, pens and pencils with him.
CORRECT: There were no books, pens or pencils with him.

INCORRECT: I do not like coffee and tea.
CORRECT: I do not like coffee or tea.

COMPARE
a) I like tea and coffee. (I like both tea and coffee.)
b) I don’t like tea or coffee. (I don’t like tea and I don’t like coffee.)

C) For emphasis, we can use EITHER – OR instead of OR; e.g.

Bring me either tea or coffee.
= Bring me tea or coffee.

2. NOR

A) We use NOR with NEITHER or A NEGATIVE CLAUSE to make a negative statement about two people or things; e.g.

i) Neither Ritu nor Ruchi was there.
ii) The sheets were never washed, nor the towels, nor his shirts.
iii) No one knows his address, nor his phone number.
iv) I can’t make head nor tail of these instructions on the packet.

B) When a verb is negated by NOT or NEVER, and is followed by a negative verb phrase (but not an entire clause), we can use any of OR and NOR; e.g.

He will not permit the change nor even consider it.
= He will not permit the change or even consider it.

C) NOR in replies

We can reply to a negative statement using NOR. We do this to show that what has just been said also applies to another person or thing. We can also use NEITHER in the same way with the same meaning; e.g.

I don’t like him. – Nor does she.
= I don’t like him. – Neither does she.

For more chapters/topics on English Grammar read the following book authored by me.

Link for buying the above book

For English Practice Sets on various topics read the following book authored by me.

Link for buying the above book