Vigilant is an adjective meaning aware and attentive; vigilante is a noun meaning someone who takes the law into their own hands (like most comic book superheroes, for example). 

From the first sentence, you know there is a fork in the road. To diverge means to extend in different directions. Although the other words sound similar, none of them has a similar meaning. 

There are only two options that convey emotional states: anxious means worried and is therefore the right choice. The only other emotional state on this list, impervious, means impenetrable. 

There is a conflict in the sentence between Jean-Paul's uncertainty and his experience. The word despite is the only way to maintain that tension logically. 

The word instinctive in the first sentence is the first clue to helping you fill in the blank. The structure of the sentence, too, should also indicate that the word you're looking for is an adjective. Automatic is the only option that fits. 

The fact that their friend is still breathing will be welcome new to the group of hikers. Therefore, they will feel relief that he has not been more badly injured. The correct choice is relieved. None of the other words are logical. 

The correct answer is No error because "its" is the possessive form of it, and here we are talking about the cover of the book, and so it is correct to use "its" in the possessive sense. When used with an apostrophe, the word "it's" is a contraction meaning "it is" or "it has." This sentence is not trying to say it is or it has, and so the best choice is no error. 

The correct answer is "The team's victory was well-deserved." A team is a singular noun, and when it shows possession it requires an apostrophe s. The word "teams" without an apostrophe means multiple teams, which this sentence does not communicate. The word "teams's" is the possessive form of multiple teams.  There should not be a comma in the middle of this sentence since it is a simple sentence with one independent clause and no dependent clauses or modifiers. 

The correct answer is "In 1929, the year the stock market crashed, many people lost their jobs." This is correct because it sets off the non-essential clause "the year the stock market crashed" with commas. Since the sentence would still make sense without this information, it is considered non-essential, and always enclosed in commas when it occurs in the middle of a sentence. It is incorrect to omit one or both commas; both are necessary. 

The correct answer is "I waited in line, gave my tickets to the agent, and boarded the plane."  This is because since we have a list of three items, we need to separate each item with a comma. One comma is incorrect, as is no commas. Leaving out the commas leads to confusion.