virtual libraries present a new paradigm for learning in school libraries ,change to past perfect tense​

Using the past perfect tense, the sentence becomes:

Virtual libraries had presented a new paradigm for learning in school libraries.

Explanation:

The past perfect tense is used to talk about actions that took place in the past before another action that also took place in the past. Let's make a simple timeline to represent that:

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past                    simple                      present                  simple              simple

perfect               past                          perfect                   present            future

For example, suppose you washed the dishes. Your mother arrived after you washed the dishes. Thus, you can use the past perfect to express the first action. The structure is subject + had + main verb (past participle):

I had washed the dishes before my mother arrived.

Having that in mind, we can change the sentence in the question using the past perfect to become:

Virtual libraries had presented a new paradigm for learning in school libraries.

expository writing is one of the most common types of writing.

1. read the following excerpt from franklin d. roosevelt's "fireside chat 19":

on the other side of the picture, we must learn also to know that guerilla warfare against the germans in, let us say serbia or norway, us; that a successful russian offensive against the germans us; and that british successes on land or sea in any part of the world strengthen our hands.

remember always that germany and italy, regardless of any formal declaration of war, consider themselves at war with the united states at this moment just as much as they consider themselves at war with britain or russia. and germany puts all the other republics of the americas into the same category of enemies. the people of our sister republics of this hemisphere can be honored by that fact.  

the true goal we seek is far above and beyond the ugly field of battle. when we resort to force, as now we must, we are determined that this force shall be directed toward ultimate good as well as against immediate evil. we americans are not destroyers — we are builders.

analyze the effectiveness of this excerpt. how does it function within the speech as a whole? how does the structure of the excerpt to convey the speech's purpose and key points? support your argument with evidence from the speech. (10 points)