If a person wants to have an enjoyable summer vacation, you need to plan for it carefully. ...

If a person wants to have an enjoyable summer vacation, you need to plan for it
  carefully.
 
  Correct any pronoun errors in the following sentences. Do nothing if the sentence is
  correct.

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Ques. 2

Because it was raining last Saturday, Dennis was forced to change his plans;
  however, this did not bother him.
 
  Correct any pronoun errors in the following sentences. Do nothing if the sentence is
  correct.

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Ques. 3

When Darwin told his son that baby whales grow ten pounds each hour, he
  smiled.
 
  Correct any pronoun errors in the following sentences. Do nothing if the sentence is
  correct.

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Ques. 4

Elizabeth decided that Robert and herself should write a sonnet.
 
  Correct any pronoun errors in the following sentences. Do nothing if the sentence is
  correct.

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Ques. 5

Every dog and cat in the place had been abandoned by (its their) owner.
 
  Underline the correct pronoun in the parentheses.

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Ques. 6

Has every zoologist in the room expressed (his or her their) opinion about why
  beavers have orange teeth?
 
  Underline the correct pronoun in the parentheses.

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Ques. 7

Neither my father nor my brother will let me borrow (his their) tools.
 
  Underline the correct pronoun in the parentheses.