 Since and for, what is the difference? For and since are prepositions used when talking about time. Let's look at the difference between the two words. For, for is used with a period of time. This is often a number plus a time word. For is used when we measure the duration of something, or how long it lasts. It has a start point and an end point, and can be used in different tenses. Here are some example sentences. I studied French in Paris for two years. This talks about a duration of two years and is in the past tense. I will be there for around two hours. This is in the future tense. They have been married for 27 years. This is in the present perfect tense. Since, since is used with a starting point or a time or date. It refers to something that started in the past and continues until now. This is mostly used with the present perfect and perfect progressive tense. For example. She hasn't eaten since two o'clock. The period of not eating started at two and continues until now. He has been working here since February. We have been married since 2016. We got married in 2016 and we continue to be married now. Thanks so much for watching. We are ITTT the leading provider for Teflon TESOL training courses. If you like this video, please subscribe by clicking that button down here and click on any of the videos here on the left for more interesting teaching tips for getting certified to teach English abroad and online.