Question 42: Mark the letter A, B, C, or D on your answer sheet to indicate the undelined part that needs correction in each of the following questions: To turn on (A) the light, I was (B) surprised at ( C) what (D) I saw.
Answer A.
To avoid repeating the same subject in the same sentence with multiple clauses, we can omit the subject in the first clause by changing the verb to -ing form.
So: to turn on => turning on.
Translation: When I turned on the light, I was amazed at what I saw
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