The use of a, an, or the is a signal that a noun is coming.
In the English language, only nouns are preceded by articles. A is used when a noun starts with a consonant (a book, a table, a bottle); an is used when the noun starts with a vowel (an apple, an umbrella, an avocado); the is used when you are referring to a particular thing (The boy I just met is called Mark.)
<span>In fact, it seems like the room and its creepy atmosphere might really be getting to our speaker. Even the rustling sound of the curtains seems sad to him .As he listens, he begins to really freak out, his head filling with "fantastic terrors."His heart starts to beat faster too; to calm himself down, he has to tell himself (twice) that the knocking sound he hears is just a visitor.<span>The more he says it though, the more we all know that it can't just be that, or at least not the kind of visitor he might be expecting…</span></span>
You cite the source(s) you used. Basically giving them credit for their work. It helps to avoid plagiarism.<span />
<span>I like to eat potatoes. They are good any way you cook them. My sister likes sweet potatoes. She cooks them all the time for her husband. However, he hates them. When we are together he gives them to me. It is our secret. You have to understand that we can never tell my sister because she would be mad at him if she knew. Her husband doesn't like the secrecy. It is his goal to learn to like sweet potatoes. I think that my sister is beginning to suspect us of something. I think he should tell my sister about the potatoes before she really gets suspicious. He thinks we should keep it to ourselves.
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