What is an easy way to teach present perfect tense so my ESL students can understand it?

The present perfect tense describes actions that occurred in the past, i.e. before now, and in an uncertain or undefined/open time period. Events it applies to can be incomplete, unspecified or recurring. Cover: 1. Why and when the present perfect is used (see https://www.ef.co.uk/english-resources/english-grammar/present-perfect/ for a good list). Contrast it with usage of the simple past tense alongside how and why they differ (simple past is used for definite i.e. specific/complete/finished actions). 2. How the present perfect is used in terms of formation; to have + past participle of main verb. I think the best way of explaining it for someone to understand is by asking them to look at the sentence in which it is used as a whole, and asking: - Is the action/event complete/finished? If Y, use simple past unless: 1. The emphasis is on the action with no specific period; “I have seen this (before)” 2. The named period in which it happened is still ongoing; “this” + time word, as in “I have practiced this month”. Also, use with “since (date)” or “for (period)” 3. The action/event is linked to what is currently happening; “I have moved (and am happy/have more space)” 4. The action/event took place recently (it has “just” happened) Here is a diagram of its usage: https://www.perfect-english-grammar.com/support-files/present-perfect-infographic.pdf I hope this helps a bit to give you some ideas!