**Rule: Understanding Idiomatic Expressions.** The idiom 'at loggerheads' means to be engaged in a dispute or conflict. Having opposing political views is a common source of such disagreement. Option (a) is the correct definition. Option (b) and (d) are the opposite. Option (c) is a literal misinterpretation.

**Rule: Understanding Idiomatic Expressions.** The idiom 'give free rein' means to grant someone full autonomy and control over something. It comes from the idea of dropping the reins to let a horse run freely. Managing a project 'as he sees fit' is the definition of having this freedom. Option (b) is the correct meaning. Option (a) is a literal interpretation. Option (c) and (d) are the opposite.

**Rule: Understanding Idiomatic Expressions.** The idiom 'in a class of one's own' means to be unique and superior to everyone else in a particular skill. Being 'far better than his competitors' is a direct explanation of this idiom. Option (b) is the correct definition. Option (a) and (d) are literal misinterpretations. Option (c) is the opposite.

**Rule: Understanding Idiomatic Expressions.** The idiom 'keep one's cards close to one's chest' means to be very secretive about one's plans or ideas. It comes from card games where players hide their cards from opponents. The fact that 'no one knows what his next move will be' is a result of this secrecy. Option (c) is the correct definition. Option (a) is the literal origin. Option (b) is the opposite. Option (d) is a possible but not necessary interpretation.

**Rule: Understanding Idiomatic Expressions.** The idiom 'make a clean sweep' has a few meanings, but in this context, it refers to getting rid of old staff or methods to make a fresh start. Hiring a 'whole new team' is a clear example of this radical change. Option (b) is the correct definition for this context. Option (a) is a literal meaning. Option (c) is another meaning of the idiom, usually in sports. Option (d) is the opposite.

**Rule: Understanding Idiomatic Expressions.** The term 'one-hit wonder' refers to a musical artist or group that is famous for only one successful song. The fact that 'they never had another popular song' is the definition of a one-hit wonder. Option (a) is the correct meaning. Option (b) is a possible part of the story, but not the full meaning. Option (c) is the opposite. Option (d) is a nonsensical interpretation.

**Rule: Understanding Similes.** The simile 'as sober as a judge' means to be very serious, sensible, and not under the influence of alcohol. A judge is stereotypically a serious figure. This seriousness inspires trust in their opinion. Option (a) is the correct definition. Option (b) is a literal interpretation of 'judge'. Options (c) and (d) are the opposite of the qualities implied.

**Rule: Understanding Idiomatic Expressions.** The idiom 'back to square one' means to have to start a process again from the very beginning because a previous attempt was unsuccessful. A failed prototype is a clear reason to start the design process over. Option (a) is the correct definition. Option (b) is a literal misinterpretation. Option (c) is an understatement. Option (d) means to quit, not to restart.

**Rule: Understanding Idiomatic Expressions.** The idiom 'put a spin on something' means to present information in a particular way, often to create a favorable or specific impression. A 'new spin' means a new angle or interpretation. Option (b) is the correct definition. Option (a) is a literal misinterpretation. Option (c) is a possible but not necessary outcome. Option (d) is the opposite.

**Rule: Understanding Idiomatic Expressions.** The idiom 'a rule of thumb' refers to a practical and approximate method for doing something, derived from experience rather than precise science. Double-checking one's work is a general principle for ensuring quality. Option (b) is the correct definition. Option (a) is a literal misinterpretation. Option (c) is incorrect as a rule of thumb is often flexible. Option (d) is the literal origin but not the modern figurative meaning.