When writing your Research essays, do not rely on the spell check function offered by your word processing software. It is indeed likely to tell you some mistakes, but certainly not all. Moreover, it may also be that emphasizes certain words that are not wrong at all. Your computer is only looking for words based on common mistakes. Sometimes we use words a little differently than we may normally do, however you computer will flag these as wrong.
Example of such words you may write on your Research essays are words that very domain specific with regards to the knowledge you are dealing with. Some Research projects use domain specific words that make sense in to other people in that area, but that your computer does not understand. There are words that agree and words that disagree with the ones next to them. The most obvious ones are double negatives. "He does not", is okay, "he does not didn't" is not okay. You computer is not going to know all of your words correct disagreements or agreements, nor will it know if you were right to insert them or not insert them. The spell/grammar check software correctly handles the agreements when the subject and verb or nouns and adjectives that depend on each other, are side by side, otherwise it is all up to you.
So check systematically the words in the dictionary (paper or web) if you have any doubt, and avoid using phrases that you are not comfortable with on your Research essay. There is a certain style and syntax that is especially needed in creating a Research term paper. Do not be foolish and copy the way that newspapers write, because they often make a lot of mistakes. Newspaper writers have very strict deadlines. If a story breaks before 12pm, they need to have it in print by 5am.
If you decide to have your Research paper written by a Research writing company then at least you can rest assured that they have plenty of time and expertise to check and recheck their work thoroughly. They are able to pick apart the details and content of the work they produce, check it, and then put it back together to make sure that every word is perfect. They have people who proofread all day long, so they know what to look out for.
If you have decided to write your own Research essay then here is a tip regarding citations, do not make them too long. They must be up to five lines, at the most. You can pick and choose the points of interest and leave some bits out so long as you do not skew the meaning of the quote into something else. Some research papers will also require you to say explicitly that you have cut down the quote/citation you have put into your text. This is so that if you misinterpreted the meaning of the citation, that the reader may be able to see why you misinterpreted it by the fact that you did not cite the entire speech, etc.