There are no errors in this sentence. The use of quotation marks is appropriate because the word "reading" is being used in an usual way in that it does not actually refer to what most people would call reading. The comma is necessary after "reading" because the phrase "When he said he was 'reading' " is an example of an introductory phrase. It explains information necessary to the context of the sentence, but is outside of the main sentence, grammatically. These types of phrases must be followed by a comma in order to separate them from the rest of the sentence. The correct answer choice is, "When he said he was "reading," he was actually referring to listening to audiobooks."

This sentence contains no errors. The sentence joins two related independent clauses without the use of a coordinate conjunction, so a semicolon should appear after the word "remarkable." The other sentences contain errors in voice (Using "was considered"), punctuation (Using a comma where a semicolon is needed), or tense (The use of "collected" instead of "she began collecting"). The correct choice is, "Many considered Helen's collection remarkable; she began collecting when she was very young."

This sentence contains no errors. It is a simple sentence, so no punctuation is necessary. The correct choice is, "Advertisers must compete in order to get in front of viewers." All of the other sentences misuse punctuation, except for one, which has a voice error ("are challenged").

This sentence contains no errors. The sentence combines two independent clauses without the use of a coordinating conjunction, so a semicolon is appropriate after the word "parent." Additionally, the phrase "while some people prefer to be very hands-on with their children" is an example of an introductory phrase, which explains information necessary to the context of the sentence, but outside of the main sentence, grammatically. These types of phrases must be followed by a comma in order to separate them from the rest of the sentence. The correct answer choice is, "what makes the ideal parent; while some people prefer to guide their children throughout their development, others prefer."

There are no errors in this sentence. The phrase "In the past few decades" is an example of an introductory phrase, explaining information necessary to the context of the sentence, but outside of the main sentence, grammatically. These types of phrases must be followed by a comma in order to separate them from the rest of the sentence. No additional punctuation is needed. The correct choice is, "In the past few decades, workplaces have been moving to a more collaborative model."

There are no errors in this sentence. This sentence contains a relative clause, "such as the Internet," that explains more about a particular word or phrase in the sentence, but is not introduced by a relative pronoun. These phrases must be introduced and completed with a comma in order to separate them from the main clause of the sentence.  Additionally, the word "increasingly" is correct because it is describing the word "rapid." Since only adverbs can describe adjectives, the correct form is "increasingly." The correct answer is, "Technology, such as the Internet, has been changing the way we work at an increasingly rapid pace."

There are no errors in this sentence. It is a basic simple sentence. Note that the word "mythology" is not correct because it would imply that there is one universal mythology shared by the many different cultures. Instead "mythologies" is appropriate to refer to the differences between the types of mythology. The correct choice is, "loved to study the mythologies of other cultures."

There are no errors in this sentence. The use of the quotation marks around "good" are appropriate because it indicates a special usage of the word - that being that "good" by this person's standards differs from average standards. No additional punctuation or changes are necessary. The correct choice is, "To be considered "good" by his standards, the product."

This sentence contains no errors. The phrase "After much deliberation" is an example of an introductory phrase, explaining information necessary to the context of the sentence, but outside of the main sentence, grammatically. These types of phrases must be followed by a comma in order to separate them from the rest of the sentence. The correct choice is, "After much deliberation, he decided to buy pink roses for his date."

There are no errors in this sentence. The phrase "According to Ancient Greek Mythology" is an example of an introductory phrase, explaining information necessary to the context of the sentence, but outside of the main sentence, grammatically. These types of phrases must be followed by a comma in order to separate them from the rest of the sentence. The correct choice is, "According to Ancient Greek Mythology, Zeus was the king of the Gods."