**Rule: Understanding Idiomatic Expressions.** The idiom 'have it both ways' refers to benefiting from two incompatible situations. The sentence uses the negative ('can't have it both ways') to state that a choice must be made between two conflicting paths: hard work and relaxation. Option (a) is the correct definition of the idiom. Option (b) is a literal misinterpretation. Option (c) is a different quality. Option (d) is a possible outcome, but not the meaning of the idiom.

**Rule: Understanding Idiomatic Expressions.** The idiom 'on the warpath' means to be in a very angry state and actively seeking to argue or fight. A cancelled flight is a common trigger for such anger and frustration. Option (b) is the correct definition. Option (a) is the literal origin. Option (c) is the opposite. Option (d) is a literal misinterpretation.

**Rule: Understanding Idiomatic Expressions.** The idiom 'by a landslide' is used to describe a victory in an election or competition that is won by a very large margin. It creates a powerful image of an overwhelming win. Option (b) is the correct definition. Option (a) and (d) are the opposite. Option (c) is a literal interpretation of 'landslide'.

**Rule: Understanding Idiomatic Expressions.** The idiom 'burn the midnight oil' means to stay up very late working or studying. It originates from a time before electricity when oil lamps were used. Having to finish an essay 'by morning' necessitates working through the night. Option (a) is the correct definition. Option (b) is a literal misinterpretation. Option (c) is the opposite. Option (d) is related but not the meaning.

**Rule: Understanding Idiomatic Expressions.** The idiom 'walk on eggshells' means to be extremely cautious in one's words and actions to avoid causing offense or trouble in a tense situation. The announcement of layoffs would create a very tense atmosphere in a workplace. Option (a) is the correct definition. Option (b) is a literal interpretation. Option (c) is the opposite. Option (d) is a possible but different reaction.

**Rule: Understanding Idiomatic Expressions.** The idiom 'a straight shooter' refers to a person who is frank, honest, and straightforward in their dealings with others. The fact that he 'will always tell you the truth' is a direct explanation of this quality. Option (b) is the correct definition. Option (a) and (d) are literal misinterpretations. Option (c) is the opposite.

**Rule: Understanding Phrasal Verbs.** The phrasal verb 'wear off' means for a feeling or the effect of something to fade away slowly. The 'novelty' or newness of a situation often diminishes over time. Option (a) is the correct definition. Option (b) is the opposite. Option (c) is a literal meaning of 'wear'. Option (d) is an unrelated action.

**Rule: Understanding Idiomatic Expressions.** The phrase 'the root of the problem' refers to the primary, underlying cause of an issue, as distinct from its surface-level effects ('symptoms'). The sentence structure itself contrasts the two concepts. Option (c) is the correct definition. Option (a) is the literal meaning of 'root'. Option (b) defines 'symptoms'. Option (d) is unrelated.

**Rule: Understanding Idiomatic Expressions.** The idiom 'sailing close to the wind' means to take risks and behave in a manner that is borderline illegal or improper. It implies that a small mistake could lead to disaster. Taking 'big risks' with company money fits this description perfectly. Option (b) is the correct definition. Option (a) is the literal origin. Option (c) is the opposite. Option (d) is a different approach to investing.

**Rule: Understanding Idiomatic Expressions.** The idiom 'open and shut' describes a case or problem that is easily resolved because the facts are clear. The sentence uses the negative ('not open and shut') to mean the opposite: that the case is *not* simple because the evidence is weak. Therefore, the idiom itself means simple and straightforward. Option (a) is the correct definition of the idiom. Option (b) is a literal misinterpretation. Option (c) describes the situation in the sentence. Option (d) is a different meaning of 'shut'.