In this sentence, the word "unbelievable" should be modifying "large" rather than "mouse," and, since "large" is an adjective, "unbelievable" must be made into an adverb, "unbelievably," to modify it. Two answer choices correct this adverb error, but only the correct answer choice does not add in any further errors. "Gnawing on a flour sack, I found the unbelievably large mouse" adds another ambiguous modifier and alters the meaning of the sentence by implying that the speaker was gnawing on a sack of flour, rather than the mouse.

The use of the word "usual" in the sentence is incorrect, as it describes the verb "took," which means it needs to take an adverb form. The only answer choice with the correct form that also keeps the intended meaning of the sentence is "The old man usually took."

The word "increasing" in the sentence is used to describe the verb phrase "being delayed." Even though these words are not the verb in the sentence, they still need an adverb form to describe them. The correct answer is "Marriages are increasingly being delayed."

Whenever you are comparing only two things, use the comparative form (usually words ending in "-er"—better, smarter, faster, and so forth). If there are three or more items, use the superlative form (usually ending in "-est"—best, smartest, fastest . . .) to designate the best one.

The expression “more worse” cannot exist because “worse” is already a superlative. The second “that” specifies which Friday afternoon in particular, as opposed to any Friday afternoon of the year.

We know that in this sentence, only two items are being compared, because the sentences begins with "Between chimpanzees and orangutans." When only two items are being compared, remember to use the comparative forms of adjectives ("more" or "-er") rather than the superlative forms ("most" or "-est").

The only answer choice that obeys this rule is "are the more intelligent, and orangutans are the more social."

We use comparative adjectives when comparing two people or things (bigger, worse); we use superlative adjectives when comparing one person or thing with three or more people or things (the biggest, the worse).

We use comparative adjectives when comparing two people or things (bigger, worse, etc.); we use superlative adjectives when comparing one person or thing with three or more people or things (the biggest, the worst, etc.). Thus, here we use the superlative adjective “the shortest.” In the first clause, we use “me” instead of “I” because “me” is an object pronoun, and “me” is the indirect object of the verb “look.”.

The use of the form "strongest" is a superlative that indicates the peak of an adjective; therefore, there can be only one "strongest boy," and the phrase needs a definite article, "the," instead of the indefinite article, "a."

"More well" is not a phrase—the comparative form of "well" is not "more well," but "better." Since we are only comparing two groups (the speaker versus the speaker's friends), "better" is the most appropriate here.