For example: I have. We contract the subject I with the auxiliary HAVE which becomes I’VE … and then you can add the past participle. Here is the list of present perfect tense contractions: I have ️ I’ve. You have ️ You’ve. He has ️ He’s. She has ️ She’s. It has ️ It’s. We have ️ We’ve. The past perfect is very similar to the present perfect because the event also started in the past. However, the difference between the events is that the past perfect event also ended in the past. This can be used with a specified time. For example, “I had studied in China last year”. This also implies the event happened a long time ago. Here are the basic differences between these two tenses: Time Specificity: The past simple is time-specific, while the present perfect is not. Relevance to Present: Present perfect actions are usually relevant to or affect the present; past simple actions do not. Time Markers: Past simple often uses specific time markers, while present perfect RULES Use after, as soon as, the moment that, until before using the PAST PERFECT simple. Use before, when, by the time before the past simple The order of phrases may be switched, but the meaning will stay the same. By the time Doris got to the party, everyone had gone home. Everyone had gone home by the time Doris had got to the party. Future perfect progressive is used to emphasize the length of time or duration of an event occurring before and up to another event in the future. Example: By the time they arrive, we will have been waiting for 4 hours! To emphasize the duration of an activity. Example: John will have been studying for 6 years by the time he finishes his exam. The past simple is used to express something that happened at a past point in time. Remember to always use a past time expression, or a clear contextual clue when using the past simple. If you do not indicate when something happened, use the present perfect for unspecified past. This tense is often used with the following time expressions: 2: Something that started in the past and continued up to another action or time in the past. The past perfect tells us 'how long', just like the present perfect, but this time the action continues up to a point in the past rather than the present. Usually we use 'for + time'. We can also use the past perfect continuous here, so we most often 3. By the time I got to the office, the meeting (begin, already) without me. My boss (be) furious with me and I (be) fired. 4. When I (turn) the radio on yesterday, I (hear) a song that was popular when I was in high school. I (hear, not) the song in years, and it (bring) back some great memories. 5. VIidLUR.