Common Grammatical Errors

grammar mistakesThough English grammar is an extremely vast subject to make generalizations and summaries about, practice shows that many students tend to make similar mistakes from generation to generation. College and university professors could probably compose charts and hit-parades of such mistakes, but for obvious reasons, this guide lists only those mistakes which occur most often.

Technicalities and Punctuation

  • Misuse of commas and apostrophes. Commas are used to mark pauses and separate ideas so readers can read with understanding. Most often commas are forgotten in lists and introductory phrases. For example, students tend to forget to insert commas in sentences like, “Today, I went to a grocery store and bought a pineapple, several kiwis, and a pound of raisins.” As for apostrophes, they should be used only in two cases: contractions (such as isn’t, won’t, doesn’t) and possession (Mike’s tablet, my cousin’s friends, man’s world, and so on).
  • Typos and spelling errors. Students, especially those from abroad, sometimes write words exactly as they sound, completely ignoring English orthography, or confusing and interchanging words that sound similar. Such words as their – there, lose – loose, its – it’s, effect – affect are confused most often.
  • Agreement of verb and subject. While students rarely experience issues with agreeing verbs with singular nouns, such as “The man was reading a book,” students still may make mistakes when agreeing such confusing words as everyone, someone, nobody, and so on. It is important to remember that all of them are singular, even if they refer more than to one individual. So, even if you are talking about a group of people, you should still say: “Everyone is happy,” or “Nobody is listening to me.”
  • Confusing past and present tenses. It often happens that students start a paragraph in the past tense, but then shift to describing events in present tense. Remember, if you have started a passage in a certain tense, you should adhere to it until you finish this passage.
  • Wrong verb endings. While students usually do not have problems with regular words with an -ed ending, it may become an issue in the case of irregular verbs. Such mistakes as “seeked” (instead of “sought”), “thinked” (“thought”), “seed” (“saw”) and so on happen more often than college professors would possibly like.

Word Confusion

  • Which and That. The difference between which and that does exist, but it is so sophisticated that many students don’t notice it. That belongs to a category of so-called restrictive pronouns. For example, the sentence “I don’t watch movies that aren’t filmed by famous directors,” shows the usage of “that” clearly: the person states that all movies filmed by not-so-famous directors don’t appeal to him or her. On the contrary, the pronoun “which” means performing a certain action. “I prefer to watch movies which were filmed by famous directors” is a clear example of the usage of which. However, this pronoun can be used in many ways, including those which have restriction.
  • Lay and Lie. The verb lay is transitive, which means it is used to show that a subject performs an action on an object. For example, “I lay my books on the bed,” or “I can’t remember where I laid down my pen.” The verb lie is intransitive, which means it does not relate to a direct object; “My dog lies on the lawn” is a typical example of the usage of “lie.” With transitive verbs, the verb needs another object to work; with intransitive verbs, an object needs a verb for it to work.
  • Who and Whom. “Who” is the pronoun of the same kind as he, she, they, and so on; it is used when a person acts as a subject in a case. “Who did that?” is a common example of this pronoun’s usage. “Whom” marks a person who is an object of a certain clause; this pronoun is similar to him, her, them, and others. For example, “Yesterday, I met a guy whom I got acquainted with during my journey across Europe.”
  • Then and Than. It is important to remember that “than” refers to comparison, while “then” is more about cause and time-relationship. Take a look at the examples below:
    1. “I like oranges more than tangerines.” Here the speaker compares two sorts of fruit and states his attitude (Comparison).
    2. “Then we can catch a cab instead of walking there.” Since two people are in a rush, they decide to save some time and go by taxi (Cause and effect).
    3. “The wind increased, and then it started raining cats-and-dogs.” First, the wind increased, and after the rain started (Time relationship).
  • Since and Because. “Because” is used to mark a cause and effect relationship between events and actions described in a text, while “since” is used to mark the time relationship. For example:
    1. “A lot has changed since I last visited my hometown.” (“Since” indicates that a person had spent some time away from his or her hometown).
    2. “Because I wanted to get good marks on the exam, I spent all my free time studying.” (“Because” indicates the reason why a person spent all their free time studying).

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Samples for Common Grammatical Errors

Word Usage Examples

Clarification of 'That' and 'Which' That is used in what's called restrictive clauses...

Mistakes: Commas and Apostrophes

Misuse of Commas Too Many Examples:"I was a bouncer, at a club, that hosted rock bands, such as The Conversations.""There was, a giant referee, in the middle, of a god named Uselferous.""...


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