Past simple osv..

The large number of different composite verb forms means that English has the richest and subtlest system of tense and aspect of any Germanic language. This can be confusing for foreign learners; however, the English system can be presented systematically by noting that each of the temporal spheres (past, present, future) distinguishes simple forms from progressive (continuous), perfect, or both.
Basic Progressive Perfect Perfect progressive
Future I will write I will be writing I will have written I will have been writing
Present I write I am writing I have written I have been writing
Past I wrote I was writing I had written I had been writing

Because of the neatness of this system, modern textbooks on English generally use the terminology in this table: where the "future" time meets the "perfect" aspect we have the "future perfect" tense. This has necessitated minor changes from older terminology. What was traditionally called the "perfect tense" is here called "present perfect" and the "pluperfect" becomes "past perfect", in order to show the relationships of the perfect forms to their respective tenses. The form wrote, which older works by linguists often called the "preterite" and older schoolbooks sometimes called the "imperfect" is here called the "past simple".