has/have + past participle form of the verb He has written a letter. They have arrived. It has stopped raining. The present perfect tense is used to talk about completed activities in the immediate past. It is often used with the adverb of time just. I have just finished my work.
Form: subject + first form of the verb I write. He writes. She writes. You write. They write. Carefully notice the marker -s in the second and third sentences. When the subject is a singular verb we add the marker -s to the verb in a simple present tense. The simple present tense is used [...]
Now read the following sentences: * I write. * I am writing. * I have written. * I have been writing. The verbs in all of these sentences refer to the present time, and are, therefore, said to be in the present tense. In sentence 1, however, the verb simply talks about the action.
Mysteries in History: From Prehistory to the Present
The award-winning author takes readers on a journey through great historical mysteries through the ages. Entertaining in themselves, the stories also show that history is not merely living, but lively. The reader who comes to the book thinking history is boring will leave with a changed outlook with regard to both the subject matter and the process of writing history.