1. The answer is B.
to prevent cramps is misplaced in the other sentences. Sentence B is clear in its meaning.
2. The answer is A. The grammatically correct sentence is this first one:
She and Louis went to see the latest Star Wars movie.
The pronoun She should be used because it is in the Nominative Case, the case used for subjects and predicate nominatives. Her is Objective Case and is only used as a direct object, indirect object, or object of a preposition. (It is also possessive case pronoun) Her is never a subject pronoun.
One way to check if you are using the correct pronoun in a compound subject such as "She and Louis...." is to say the sentence aloud without the noun subject.
e.g. "Her went to see the latest Star Wars movie." Your ear will tell you this is wrong, also, as well as knowledge of pronoun case.
3. The answer is A. In this sentence, the concept here is that of an Agreement between Personal Pronouns and Indefinite Pronouns.
Each of the girls who played soccer injured her knee in the play-offs.
Confusion often comes when a phrase such as the prepositional phrase "of the girls" comes between the indefinite pronoun and the personal one. But the indefinite pronoun each is the subject and the antecedent must, therefore, agree with each. Therefore, since each (meaning "each one") is singular, the pronoun her, which is also singular, is used.
4. The answer is C. This is the grammatically correct sentence. The participial phrase is preceded by a comma.
- The first sentence is incorrect because a period is used after body, making "Causing problems with heart rate and respiration" to become a sentence fragment since participial phrases cannot be sentences.
- The second sentence is incorrect because a semi-colon is used. Semi-colons separate independent clauses, not participial phrases.
According to Owl Purdue Writing Lab, here is the reason that a comma is used before the participial phrase beginning with "causing":
If a participial phrase comes at the end of a sentence, a comma usually precedes the phrase if it modifies an earlier word in the sentence but not if the phrase directly follows the word it modifies.
Stress is the "earlier word," so the participial phrase, which comes at the end of the sentence needs the comma.
5. The answer is D. All are incorrect for these reasons:
- The first choice is incorrect because there is a comma splice. A semi-colon must be used between two independent clauses such as are in this first sentence.
- The second choice because it is a run-on sentence. (There is no punctuation between the two independent clauses.)
- The third choice is incorrect since a comma is incorrectly used before the word because.
According to The Chicago Manual of Style, a comma is only used before because when the reason that follows is unnecessary. In this sentence, of course, the reasons why the digital camera is changing the photography business are clearly needed.