Directions: Fill in the blanks in the following sentences with the correct…

Solution

Correct answer: 'Each' (to form the phrase 'each other').

Explanation:

• Why 'each' is correct: 'each other' expresses a reciprocal (mutual) action between two items. In this sentence, the two knees act on one another, so 'each other' is appropriate.

• Improved full sentence: He was so afraid that his knees knocked against each other. (A shorter alternative is: He was so afraid that his knees knocked together.)

• Why the other choices are wrong:

  • "Every" would normally lead into "every other," meaning "alternate," which does not express a mutual action between two body parts.

  • "One" by itself does not form the required reciprocal phrase. The phrase "one another" is generally used for mutual actions among more than two people or things.

  • "None" does not convey a reciprocal relationship and therefore does not fit.

• Usage note: Traditionally 'each other' is used for reciprocal actions between two entities and 'one another' for more than two, though in practice they are often used interchangeably. Examples:

  • Two people: The two siblings love each other.

  • More than two: The students thanked one another.