'Everything' refers to all the persons, places or things involved in an action. It is followed by a singular verb.
- It looks different.
- Everything looks different.
In an affirmative (positive) sentence, 'anything' means 'all things'.
- I will do anything for you. (= I will do all things for you)
In a question, 'anything' means 'something' or 'any thing (even something small or insignificant)':
- Is there anything (= even something small) that I can do to help?
In a negative sentence however, 'anything' means 'nothing at all': not + anything = nothing.
- I don’t know anything about it. (= I know nothing about it)
We use 'each' to refer to individual things in a set or group: "Each apple costs $1". Since 'each' refers to individual things, it is followed by a singular verb.
- Each + singular noun: Each uncle gave me a present for my birthday.
- Each of + plural noun: Each of my uncles gave me presents for my birthday.
We use 'every' to refer to a group of similar people or things: "Every library I have been to is quiet". Since it refers to one group, it is followed by a singular verb.
- Every boy in the class went to the party. (= all the boys went)
- The bus leaves every hour. (= hourly)
Unlike 'each', 'every' does not refer to two things in a set:
- There are five fingers on each hand. (= on each of your hands)
- There are five fingers on every hand. (= on everyone's hands)