Present+Perfect+vs+Past+Simple

[|Contrast (explanation)]

Exercises on Simple Past and Present Perfect Simple

 * Certain time in the past or //just// / //already// / //yet//: [|Exercise 1], [|Exercise 2]
 * Certain event in the past or how often so far: : [|Exercise 3], [|Exercise 4]
 * Emphasis on action or result: [|Exercise 5], [|Exercise 6]
 * Mix: [|Exercise 7], [|Exercise 08]
 * Exercise on the text [|Grand Canyon]
 * Exercise on the text [|Edinburgh]

Tests on Simple Past and Present Perfect Simple

 * [|Test 1]
 * [|Test 2]
 * [|Test 3]