1. We are living in a world which is full of wonderful things.
2. We are living in the world which is full of wonderful things.
(In the sentence, do we have to use 'a world' or 'the world?' What is the difference between them? Do we have to use 'a world' here?)
The use of "a" implies someplace in general ... could be anywhere.
The use of "the" implies one particular place.
This won't hold true every single time, but it'll come close. Between these two sentences, the first one is better.
In the given sentences, both "a world" and "the world" are grammatically correct and acceptable. However, they convey slightly different meanings.
1. "We are living in a world which is full of wonderful things."
In this sentence, "a world" refers to any unspecified or general world that is full of wonderful things. It implies that there are multiple worlds or possibilities where wonderful things exist.
2. "We are living in the world which is full of wonderful things."
In this sentence, "the world" refers to a specific world, often understood to be the world we inhabit or the current reality. It suggests that there is only one world or specific context in which wonderful things exist.
So, the choice between "a world" and "the world" depends on the intended meaning and context you want to convey in your sentence. If you want to emphasize that there are multiple possibilities or worlds with wonderful things, you could use "a world." If you want to highlight the world we are currently living in as the one with wonderful things, you could use "the world."