Writers like to assume that readers can read minds. Would you know what I mean if I were to write “Look at this!” or “Look at that!”? You would not know in advance, which is why you would need to investigate. In writing, this is not enough, because your readers are one step removed from your viewpoint.
INCORRECT
- I keep showing them this, and they don’t understand.
- She couldn’t believe he was going over that again.
- It is because of these that our work is never done.
CORRECT
In each case, the words this, that, these, and those need a clarifying noun. “I keep showing them this balance sheet” is quite clear; for all we know, “I keep showing them this” could be in reference to a cup of coffee. If he is “going over that again,” it might be helpful to know that he was asking her, once again, to get married. Be specific, and all will be clear.
MORE TO KNOW
These words are demonstratives; they demonstrate or point something out. When paired with a noun, they become demonstrative adjectives because of their indication of something specific. The difference between “the books,” “these books” (nearby), and “those books” (in the distance) is that with the latter two, we know exactly which books are being discussed.