Tourists can see geysers, hike trails, go bird watching, or take nature photographs. This sentence is in an active voice because of the phrase “Tourists can see”. This shows the subject acting upon something rather than being acted on as in the other choices. The other choices are all a passive voice because of the phrasing “will be”.

The Savings Bank in Ashville, Ohio was robbed in August 2015 by John Morgan and his girlfriend. Photos of the crooks and the money were taken and posted to social media. This answer choice is in the passive voice, “was robbed” and “were taken and posted” are both passive and the subject is being acted upon. The other choices use active voice word choices, “robbed”, “took photos”, “posted photos” are all showing the subject(s) performing the action.

In 1815, Mount Tambora erupted on Sumbawa, an island of modern-day Indonesia, and killed 100,000 people. If a sentence is in an active voice, the subject performs the action. In the correct answer choice, the phrases “Mount Tambora erupted” and “killed”  are in an active voice and the subject (Mount Tambora) is performing the action. The other choices are in a passive voice and the subject is receiving the action.

In the passive voice sentence the phrase “is visited” shows the subject being acted upon. To change the sentence to active voice the subject must perform the action. In the correct sentence choice the phrase “tourists visit” is in active voice and the subject (tourists) is performing the action.

Answer: “he were” Statements made in a wishful, hypothetical sense should use the subjunctive mood, which for the verb “to be” (is, was, were, have been) means that you use the tense “were.”  A way to remember the need for the subjunctive mood in these hypothetical situations (e.g. “If I were an astronaut” or “I wish she were here”) is that they’re hypothetical, so they didn’t actually happen.  Therefore, a “unique” verb form helps to clarify that.

Answer: “that she stay”  When someone commands, recommends, demands, mandates, etc. that something happen, the sentence often uses the “imperative mood.” The imperative mood uses a structure of Recommend (or demand, etc.) + That (Person) + Infinitive Form of Verb, Minus “to.”  Which seems like an odd math problem but consider these options:

The teacher recommended that Julie study… (the infinitive form is “to study” so the Imperative Mood is “study”)

The rulebook mandates that each player wear a helmet (the infinitive form is “to wear” so the Imperative Mood is “wear”)

For this sentence, the doctor recommends that something happen, so the imperative mood is “the doctor recommends that she stay” (the infinitive form is “to stay so we’ll use “stay”). 

Answer: “NO CHANGE”  When sentences use commands like “requires,” “mandates,” or “demands,” they tend to take two forms:

Command + infinitive verb (e.g. “The rulebook requires each player to wear a helmet”)

Command + that + imperative mood (e.g. “The rulebook requires that each player wear a helmet”)

With the imperative mood, the verb must follow the same form as the infinitive (“to wear”) just minus the word “to.” So here the original answer properly follows the imperative mood: “The rulebook mandates that each player wear” because the infinitive form is “to wear.” 

NO CHANGE. Statements made in a wishful, hypothetical sense use the subjunctive mood, which for the verb “to be” (is, was, were, have been) means that you use the tense “were.”  Even though this event is to take place in the future, the conditional/hypothetical aspect of the event means that you should use the subjunctive mood “I wish you were coming” or another form such as “I wish that you could come” (where “could” serves the purpose of noting that the event isn’t happening much like the subjunctive “were coming” does).

The phrase “demanded that” here signifies that what follows should be in the imperative mood, which requires the “bare infinitive” form of the verb (the form “to come” without the word “to”). So the correct answer is “the police officer demanded that the suspect come out…”  Note that among the incorrect answer choices, “comes” would be correct if it did not follow a command but since the word “demanded” requires the imperative mood, “comes” is incorrect here.  With “must come” note the redundancy: the word “demanded” already signifies that the suspect’s action “must happen” in the police officer’s mind. Do not use words like “must” or “should” directly adjacent to the verb in an imperative mood situation.  And “is coming” is something that a police officer could observe, but cannot demand - a demand is something that should happen next, while “is coming” means that it’s already happening.

 This sentence sets up a hypothetical situation in the past: we know that she didn’t spend as much time studying as she should have, but “if she had” she “probably would have” gotten the result she wanted.  The order of events is also important: since this hypothetical sequence is that she would have had to 1) spend more time studying so that, next, she could 2) earn the extra points she needed to get an A, the past-perfect tense “had studied” sets the studying further back in time than the earning of points.  The answer “had studied” properly uses the subjunctive mood and a back-in-time past perfect verb tense to convey the proper timeline.  Note that among the incorrect choices, “could spend” uses a tense that looks at the future and “spends” is a verb in the present, but you need a verb in the past.  And “was to spend” botches the need for the subjunctive mood (the conditional subjunctive would call for “if she were to spend”) and is also forward-looking in time.