Con correcciones

1. Present and Past Perfect
Reading and Writing
Unit #9

2. The Passive Voice
• Active and passive voices are used in English to
express actions.
• While in the active voice the subject is the doer, in
the passive, the subject receives the effects of the
action. Thus, only transitive verbs (those that take
a direct object) can undergo the passive
transformation.

3. • Active: Environmentalists have presented a great solution.
subject verb direct object
• Passive: A great solution has been presented (by environmentalists).
roof.
subject verb agent
In the sentence in the active voice, the primary focus is on the
subject (the agent or doer of the action). In the passive
voice, the focus is on the object of the sentence.

4. • No part at all of the verb form in the active
sentence can be deleted in the corresponding
passive one. Therefore, the modal
auxiliaries, the have plus past participles,
and the be plus –ing forms that appear in an
active sentence will appear in the pasive one.
• Although there is a change in word order—and
sometimes new elements—the passive sentence
always preserves the meaning of the active
sentence, and what really occurs is just a change
in emphasis.

5. When to Use the Passive Voice
• To signal that the performer is unknown or
obvious.
The investigation had been carried on in
Germany.
• To hint that the “doer” is a general group.
Lions have been protected.

6. • To avoid mentioning the performer of the action.
The concert had been given inside the
cathedral.
• To place emphasis on the receiver rather than on the
performer of the action.
The thief has been put in jail by the police
officer.
• To describe a scientific experiment or process.
The plants have been labeled for further
research.

7. The Passive Voice with Present and
Past Perfect
Person/
object
+
have
has
had
+ been +
past
participle of
verb

8. • To form the passive voice with the present perfect
use have/has + been + past participle.
Active Passive
Present Perfect
WWF has created new
regulations.
New regulations have
been created by WWF.
People have hunted fewer
animals.
Fewer animals have been
hunted.
Scientists have presented a
number of solutions.
A number of solutions have
been presented .

9. • To form the passive voice with the past perfect
use had + been + past participle.
Active Passive
Past Perfect
People had hunted the
American bison to near
extinction.
The American bison had
been hunted to near
extinction.
People had hunted animals
mostly for food.
Animals had been hunted
mostly for food.

10. Practice. Choose the correct verb form to complete each sentence.
1. I have finished the job. / The job .............................. by me.
a) have been finished
b) has been finished
c) had been finished
2. The cat had drunk the milk. / The milk ............................ by the cat.
a) have been drunk
b) has been drunk
c) had been drunk
3. The girl has plucked the flowers. / The flowers ...................... by her.
a) have been plucked
b) has been plucked
c) had been plucked
4. I had watched that movie. / That movie .......................... by me.
a) have been watched
b) has been watched
c) had been watched

11. Practice. Choose the correct verb form to complete each sentence.
1. I have finished the job. / The job .............................. by me.
a) have been finished
b) has been finished
c) had been finished
2. The cat had drunk the milk. / The milk ............................ by the cat.
a) have been drunk
b) has been drunk
c) had been drunk
3. The girl has plucked the flowers. / The flowers ...................... by her.
a) have been plucked
b) has been plucked
c) had been plucked
4. I had watched that movie. / That movie .......................... by me.
a) have been watched
b) has been watched
c) had been watched