To improve your vocabulary there are some important things that you need to do. One is to see usage of familiar words in new phrases. This will help you to learn how words can be used in different contexts. Secondly, note down any new words or phrases that you come across. You can use these later in your writing. Practice, revise and review, this is most important if you want to improve your vocabulary. The more you practice the better will be your writing skills. But we have saved the most important advice for the last, which is read as many novels, newspapers, magazines, posts and blogs that you can. There’s an inexhaustible supply of reading material in whatever genre or kind of writing that interests you. The more you read the more will your vocabulary improve. Also, your knowledge will improve and as you learn new things your vocabulary will improve. Yes, online grammar checker will improve your vocabulary but to a limited extent. As all it will be doing is displaying your grammar and spelling mistakes and suggesting changes. Therefore, your vocabulary will improve only in spelling words correctly or using them correctly in a sentence. Remember online grammar checker is a checker and not a teacher. But if you follow the tips we have given you your vocabulary and your command over the English language will improve. You have to be well-read to master the English language, and I am afraid there are no shortcuts to that. So if you spend just one hour a day in reading anything that is interesting you will see that soon you will be using new words in your speaking and writing. Everyone has some particular area of interest; sports, fashion, travel, entertainment and so forth. Advancing your knowledge about your area of interest will eventually help in improving your vocabulary.