I still can't speak or write in perfect English, but my English has tremendously improved since I joined the BPO industry.
Here are a few errors I used to make and I still observe fluent English speakers make these errors:
1. %u201CDid not Knew%u201D: This is the most common error people make while speaking. Whenever we have to say "I did not know about...", we end up saying "I did know knew" or "I did not had" instead of "I did not have". We need to understand that when we used "did", we have to use "have", "know" or present tense instead of a paste tense.
2. The word "Anyways": We need to realize that in English dictionary, there is no such word as "Anyways". Most of us have a habit of saying "Anyways" either at the beginning or at the end of a sentence. The correct word is %u201CAnyway%u201D, that%u2019s without an S. When we say %u201CANY%u201D, we mean one of many therefore we need to use %u201Cway%u201D instead %u201Cways%u201D. %u2018Way%u2019 is singular, %u2018Ways%u2019 is plural.
3. One of those Day: The correct words would be %u201COne of those days%u201D. We tend to use a singular form at the end instead of a plural form when we say %u201COne of those thing%u201D. It should always be a plural form at the end when we are pointing out one from a bunch of things or a number of days, therefore it should %u201COne of those things%u201D