闭门造车:
Meaning: Make a car behind closed doors; work in isolation from reality.
Explanation: This idiom warns against working in isolation without considering external circumstances, leading to impractical results.

背水一战:
Meaning: Fight with one's back to the river; fight to the death.
Explanation: Originating from a military strategy where soldiers had no retreat, it means to fight with determination and no option to retreat.

百发百中:
Meaning: Always hit the target; consistently successful.
Explanation: Literally "hundred shots, hundred hits," it describes someone who is extremely accurate and successful in their endeavours.

水落石出:
Meaning: The truth will come to light eventually.
Explanation: Literally "when the water recedes, the rocks emerge," it means that hidden truths will be revealed in time.

狼狈为奸:
Meaning: Partnership between bad people to do bad things.
Explanation: Literally "jackals work together for evil," it describes the collusion of villains in committing misdeeds.

积少成多:
Meaning: Small efforts over time can lead to significant results.
Explanation: Literally "accumulate little by little to become much," it encourages consistency and persistence in efforts.

济济一堂:
Meaning: A grand assembly or gathering of many distinguished individuals.
Explanation: Describes a scene where many talented and prominent people are gathered together in one place.

虎头蛇尾:
Meaning: Starts strong but ends weakly or disappointingly.
Explanation: Literally "tiger's head, snake's tail," it describes efforts or projects that begin with great momentum but fail to sustain it.

光阴似箭:
Meaning: Time flies like an arrow.
Explanation: This idiom emphasizes how quickly time passes, urging people to make the most of it.

坐井观天:
Meaning: Having a narrow or limited perspective.
Explanation: Literally "sitting in a well and looking at the sky," it means to have a limited view of the world due to a confined perspective.

自相矛盾:
Meaning: Self-contradictory.
Explanation: Describes a situation where one's actions or statements are inconsistent or conflicting, originating from a story about a merchant who boasted both the invincibility of his shield and the penetrative power of his spear.

纸上谈兵:
Meaning: Unrealistic or impractical ideas, especially in strategy.
Explanation: Literally "discussing military tactics on paper," it warns against plans that look good on paper but are unworkable in practice.

张灯结彩:
Meaning: Decorate festively.
Explanation: Literally "hang lanterns and festoons," it describes the decorations during celebrations, indicating a festive atmosphere.

远交近攻:
Meaning: Make alliances with distant states and attack nearby ones.
Explanation: A strategic approach in diplomacy and conflict, this idiom emphasises the benefits of allying with distant powers while focusing on local conquests.

迎刃而解:
Meaning: Solve a problem easily once the main point is addressed.
Explanation: Literally "to resolve upon encountering the edge of a blade," it means that once the crucial issue is tackled, the rest falls into place.

雪中送炭:
Meaning: Providing timely help or support.
Explanation: Literally "sending charcoal in the snow," it signifies giving help when it is most needed and appreciated.

幸灾乐祸:
Meaning: Rejoicing at another's misfortune.
Explanation: This idiom describes the schadenfreude of taking pleasure in someone else's troubles or failures.

相见恨晚:
Meaning: Regret of not meeting someone earlier.
Explanation: Literally "hate to meet so late," it expresses the sentiment of wishing one had met someone much earlier in life.

万紫千红:
Meaning: A scene full of vibrant colours.
Explanation: Describes the beauty of spring with thousands of purples and hundreds of reds, symbolising a multitude of beautiful things.

天长地久:
Meaning: Everlasting and enduring.
Explanation: Literally "as long as heaven and earth," it signifies something that will last forever, often used to describe eternal love or friendship.