case, circumstance, condition, position, situation, state 区别

Case: 情况（例证，事实）。
eg. In this case time has not been taken into account.

Circumstance:情况（指某事或动作发生时的情况，多用复数）。
eg. The circumstances are now unfavorable to the enemy.

Condition：常用词，用作单数形式，表示人或物目前所处的真实具体状态，尤指内在状态，可与state替用；
eg. The doctor says his condition is better.
用作复数形式时，笼统地表示一般状态。
eg. Conditions have changed greatly since my last visit to his factory.

Position: 有利的状况（如竞争中或战争中的）; (尤作单数)处境，情势（尤指影响某人行为的能力）。
eg.I am not in a position to help you.

Situation: 一般用词，尤指处于某时期的状况，处境，局面，形势。指各种具体情况综合起来的状态，多指危急或重大的事态，强调外部因素对该事态的影响，常用作单数形式。 eg. The international situation is favorable to us.

State: 常用词，只人或物所处的外表、心理、健康及所处的情形等方面的情况，但不如condition具体，只用作单数形式。
eg. The house was in a dirty state.