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Past, Present, and Future The three tenses that are most easily identified, and that anybody with basic English grammar skills likely already knows, are past, present, and future. These tenses are fairly self-explanatory. Past tense denotes something that occurred in the past. Present tense denotes something that is currently happening, or that is ongoing. Future tense denotes something that will occur in the future. These examples should give you a pretty clear idea of the differences between the three. Past: I walked. Present: I walk. Future: I will walk

Well, the situation you want to talk about usually means you would use a limited amount of tenses to express it. For example, if you talk about future plans, then of course you use forms for the future: will, be going to, be about to, be to, and so on. You would understand the slight differences between them. If you're talking about the past, then you use past tenses. You wouldn't use present perfect while talking about last weekend, for example. It gets more sophisticated as you learn, but the borders are there. In English, you wouldn't make a jump in tense (eg. from present tenses to past) without giving some time indication.

Try to read from different sources and do all exercises! It's pretty easy, but needs much practice. For example englishpage is a good site that I used.

From my experience, I always felt confused by using a grammar book. Instead, I would write all the verbs I used in Spanish(my native language) and I began translating them to English. My native friends would correct them and pronounce them for me. Try using a verb conjugation app and memorize the verbs you think you will need. Also try reading stories and pay attention to the verb tenses =)