positive

Compared meaning: feeling confident or hopeful about something (adjective).

比较义项：对自己、某种情况或结果感到乐观、自信或放心（形容词）。

• positive 本词

  Positive describes a hopeful, optimistic outlook about a situation or the future, not confidence in one's own ability or relief from worry; often paired with 'about' or 'stay/remain positive'.

  positive 表示对某种情况或未来持乐观、充满希望的态度，而不是对自己的能力有自信，也不是因外界安慰而消除担忧；常与“about”搭配，或用于“stay/remain positive”这类表达。

  She stayed positive about the interview, even though she was nervous.

  尽管她很紧张，她对这次面试仍保持乐观。

• assured

  Assured describes self-confidence in one's own ability or manner, coming from within, not optimism about outcomes or relief after someone else removes a worry.

  assured 表示对自己的能力或方式有内在的自信，而不是对结果持乐观态度，也不是因他人安慰而放下心来。

  Her assured manner during the presentation impressed the entire board.

  她在演讲中表现出的自信从容打动了全体董事会成员。

• reassured

  Reassured describes the relief felt after someone else removes a specific worry or fear; it implies a prior state of anxiety that has just been eased.

  reassured 表示因他人消除了某个具体的担忧或恐惧而感到放心，暗示此前处于焦虑的状态，刚刚被安抚下来。

  After the mechanic checked the brakes, she felt reassured about the long drive.

  机械师检查完刹车后，她对这次长途驾驶感到放心了。

Positive, assured, and reassured all describe a good mental state, but the source differs. Positive describes a hopeful, optimistic attitude about a situation or the future. Assured describes self-confidence in one's own ability. Reassured describes relief felt after someone else removes a specific worry.

这三个词都能表示某种积极的心理状态，但来源和方向不同：positive 指对情况或未来持乐观态度；assured 指对自身能力或表现的内在自信；reassured 指因他人的安慰或保证而消除了先前的担忧，感到放心。这里不比较 positive 表示“确定的”或数学中“正数”的义项，也不比较 assured 表示“确定的、有保证的”这一义项。

Compared meaning: certain or confirming 'yes' (adjective).

比较义项：肯定的、确定的（形容词）。

• positive 本词

  Positive expresses personal certainty or confidence about a fact, used with 'be positive that/about'; it does not describe someone else's answer as a 'yes'.

  positive表示说话人对某件事实的个人确信或把握，常用于“be positive that/about...”结构；它不用来把别人的回答描述为“是”。

  I'm positive I locked the door before we left the house.

  在我们离开家之前，我确信自己锁了门。

• affirmative

  Affirmative describes an answer, vote, or response that means 'yes' or shows agreement; it is formal and used mainly for replies, not personal certainty.

  affirmative用来描述表示“是”或表示同意的回答、投票或答复，语气正式，主要用于回复场合，而不是表达个人的确信。

  The pilot replied 'affirmative' when asked to confirm the new heading.

  被要求确认新航向时，飞行员回答“肯定”。

Positive and affirmative both relate to certainty, but they apply differently. Positive expresses a person's own confidence about a fact, used with 'be positive that'. Affirmative describes an answer, vote, or response that means 'yes'; it is formal, used mainly for replies, not personal certainty.

这两个词都可译作“肯定的”，但positive强调说话人自己对某事的确信和把握，常用于“be positive that/about...”结构；affirmative强调对方给出的回答、投票或表态是“同意/是”，语气更正式，多用于回复场合。positive还有“积极乐观”、“（检测结果）阳性”等其他常见意思，这里不作比较。

Compared meaning: a number greater than zero (adjective).

比较义项：数值为正的（大于零）（形容词）。

• positive 本词

  The standard, general-purpose word for a number greater than zero; used freely in math, science and everyday speech without any special context.

  表示“大于零的数”最通用、标准的词，可自由用于数学、科学及日常口语，没有特殊语境限制。

  Any positive number multiplied by itself gives a positive result.

  任何正数自乘后的结果仍然是正数。

• plus

  Less common and more restricted; typically used for temperatures, as the opposite of minus, rather than as the default word for positive numbers in general.

  较不常用，使用范围更窄，通常用于温度（作为 minus 的反义词），而不是表示正数的默认用词。

  The overnight low was a plus three degrees, just above freezing.

  夜间最低气温为正三度，刚好在冰点以上。

Positive and plus can both describe a number greater than zero, but positive is far more common. Positive is the standard word, used in math, science, and daily speech. Plus is less common, mainly used for temperatures, as the opposite of minus.

这两个词都可以表示“数值大于零”，但 positive 是通用、标准的说法，可自由用于数学、科学及日常语境；plus 则较不常用，多见于温度、成绩等特定场合，语气也更口语化。这里不比较 positive 表示“积极的、乐观的”这一义项（如 stay positive），也不比较 plus 作介词表示“加上、外加”的用法（如 twenty dollars, plus a fee）。