All English verbs have three perfect tense forms: past perfect, present perfect, and future perfect tense, and they include the helping verbs have, has, had, shall, or will. But since past and present perfect are more common, let's look at them more closely.
Past perfect tense describes an action that took place in the past before another past event, and it is formed with the helping verb had and the past participle form.
Before he left his job, Mike had written a letter of resignation.
Past perfect can be used in brief flashbacks of stories told in past tense. This will let readers know which events occur in the flashback rather than the main plot. But past perfect becomes a problem when it is used interchangeably with simple past tense verbs. It can be difficult trying to piece together the order of events when had slips in and out of the narrative at inappropriate times.
Present perfect is used to describe (1) an event that occurred at an indefinite time in the past or (2) an action that began in the past and continues into the present. This tense is formed by combining have or has with the past participle.
We have tried to contact her several times without receiving a response.
Progressive tenses show actions that are in progress or continuing and are formed by adding the appropriate form of the verb to be to the present participle. Both simple and perfect tenses can be made into progressive forms. However, for the sake of brevity, the examples below only illustrate the progressive form for simple tenses.
Past progressive: The band was playing the same set list throughout the tour.
Present progressive: The band is playing the same set list throughout the tour.
Future progressive: The band will be playing the same set list throughout the tour.
Final Word on Verb Tense
As I mentioned before, the context of your writing will dictate the verb tense you need. When a shift is required, make sure it is done smoothly. In your editing phase, watch for perfect and progressive tenses that found their way into situations where simple tenses would be better. And if you still struggle, have someone else look at your work to point out confusing passages.