الخطوة 1اختر الخيار الصحيح
الخطوة 2أضف التدريبات التي تعجبك إلى المفضلة
To discover is to find that which existed before but was unknown, and to invent is to create that which didn't exist before.
If we are speaking of the result of a past action rather than of the action we must use the present perfect tense. When somebody says, I have seen Panthenon, he or she is not thinking so much of the past act of seeing it, as the present result of that past action.