There are some common mistakes in English grammar that people cannot avoid of making them.
If you are having an informal conversation and you make these mistakes it may be all right to do so, since the listener will get your point but if it is kind of professional and formal situation making such mistakes is not very good for you. By avoiding these common mistakes, your grammar proficiency can be improved and you look wiser in the eyes of others.
Everybody may know this basic grammar rule that the subject/ verb agreement should be applied. Which means if the subject is singular the verb should follow and if it is plural the verb should be plural too. For example: The girl is crying. NOT The girl ARE crying. Also, subjects such as “ nobody “ and “ everybody “ can misled some people. These nouns are singular where their meanings refer to more than one person. So you should say “ everybody WAS laughing “ not “ everybody WERE laughing “.
Mixing up past and present tenses:
This error mostly happens in writing fictions or stories. When one starts writing and telling and describing event, one should keep the tense with the same tense throughout the writing. If you start with the present tense keep going with the one and if you are telling the story in past tense keep that tense from beginning to the end. The only exception that you can use past tense in your present tense writing is if you clearly state that this happened some time in the past time, for example say “ this event happened five years ago and even then people watched TV….”.
Apostrophes are usually used for two reasons: to denote a letter deleted from contractions (i.e. won’t instead of will not) or to express possession (A toy is the boy’s best present). It is however a common grammatical mistake nowadays for people to misuse apostrophes to express plural tense. So do not write “Only dog’s should eat dog-food” instead write “Only dogs should eat dog-food”.
Know the correct spelling of the past verbs:
Try not to make such mistakes. Most of the verbs in past forms are ended with “ ed “ like watched, picked or liked; however there are other forms of past verbs written. Knowing the right spelling is a must. Otherwise you get misunderstood.
Misuse of commas:
Commas are basically used to indicate to readers that they need to take a break before proceeding with the rest of the sentence. A common mistake is using them in the place of periods. If by any chance the second part of the sentence can stand on its own, then you better use a semi-colon or split it into two. Confusion of “It’s” and “its”: This is one of the commonest typos in common writing, especially in descriptive writing. “Its” does not follow the rules for possessives as mentioned above. The apostrophe can only be used when contracting “it is”. So write “Your phone has lost its value” instead of “Your phone has lost it’s value.
There can be other confusions too but these are the most common ones made by English learners.