constant

adj.

1. 连续发生的；不断的；重复的
   happening all the time or repeatedly
   1. constant interruptions
      无休止的干扰
   2. a constant stream of visitors all day
      整天络绎不绝的游客
   3. Babies need constant attention.
      婴儿一刻也离不开人。
   4. This entrance is in constant use.
      此入口经常使用。
2. 不变的；固定的；恒定的
   that does not change
   1. travelling at a constant speed of 50 m.p.h.
      以每小时50英里的恒定速度行驶

noun

1. 常数；常量
   a number or quantity that does not vary

1. ADJ 持续不断的;重复的;一直存在的
   You use constant to describe something that happens all the time or is always there.
   1. She suggests that women are under constant pressure to be abnormally thin...
      她暗示说女性总是处在保持身材异常瘦削的压力之下。
   2. Inflation is a constant threat...
      通货膨胀始终是个威胁。
   3. He has been her constant companion for the last four months.
      4个月来，他一直陪伴在她身边。
2. ADJ-GRADED 恒定的;不变的
   If an amount or level is constant, it stays the same over a particular period of time.
   1. The average speed of the winds remained constant.
      平均风速保持稳定。
3. N-COUNT 恒定物;常数；常量；常项
   A constant is a thing or value that always stays the same.
   1. In the world of fashion it sometimes seems that the only constant is ceaseless change...
      在时装界，有时似乎唯一永恒不变的东西就是不断的变化。
   2. Two significant constants have been found in a number of research studies.
      若干研究已经发现了两个重要常量。

You can use constant, continual, and continuous to describe things that happen or exist without stopping. You describe something as constant when it happens all the time or never goes away. He was in constant pain. ...Eva's constant criticism. Continual is usually used to describe something that happens often over a period of time, especially something undesirable. ...his continual drinking. ...continual demands to cut costs. If something is continuous, it happens all the time without stopping, or seems to do so. ...days of continuous rain. ...a continuous background noise.
constant, continual 和 continuous 均可用来描述不断发生或一直存在的事物。constant 表示一直在发生或从未消失：He was in constant pain (他的疼痛一直没有消停)，Eva's constant criticism (伊娃没完没了的批评)。continual 通常用来形容一段时期内经常发生的事，尤其是令人讨厌的事：his continual drinking (他经常饮酒)，continual demands to cut costs (不断要求削减成本)。continuous 表示一直没有间断，或者貌似如此：days of continuous rain (淫雨霏霏的日子)，a continuous background noise (持续不断的背景噪音)。

1. They will have to bear the misery of living in constant fear of war
   他们不得不忍受长期生活在战争恐惧中的痛苦。
2. The constant repetition of violence has blunted the human response to it
   反复出现的暴力事件使人们的反应都变得麻木了。
3. The capital is still under constant bombardment by the rebel forces.
   首都仍在遭受叛军的持续轰炸。
4. Fred had been her constant companion for the last six years of her life
   在她生命的最后6年，弗莱德一直是她忠实的伴侣。
5. We conceive of the family as being in a constant state of change
   我们认为家庭处于不断变化之中。
6. She suggests that women are under constant pressure to be abnormally thin
   她暗示说女性总是处在保持身材异常瘦削的压力之下。
7. Inflation is a constant threat
   通货膨胀始终是个威胁。
8. He has been her constant companion for the last four months.
   4个月来，他一直陪伴在她身边。
9. The average speed of the winds remained constant.
   平均风速保持稳定。
10. In the world of fashion it sometimes seems that the only constant is ceaseless change
    在时装界，有时似乎唯一永恒不变的东西就是不断的变化。
11. Two significant constants have been found in a number of research studies.
    若干研究已经发现了两个重要常量。
12. He would have a nurse in constant attendance day and night.
    会有一位护士日夜不间断地陪护着他。
13. Throughout the house, the views are a constant source of surprise and delight
    从房子各处看到的景色不断给人以惊奇和欣喜。
14. People are rejecting this constant diet of despair.
    人们开始拒绝这种没完没了的绝望情绪。
15. The dynamic of the market demands constant change and adjustment
    市场要有活力，需要不断地改变和调整。
16. His body is honed and kept in trim with constant exercise.
    他经常运动，以锻炼身体和保持身材。
17. Leaving aside the question of privacy, constant surveillance can be remarkably convenient.
    如果不去管隐私问题的话，实施不间断监视其实是非常便利的。
18. My life has been music, and a constant search for it has been the mainspring of my life
    我以音乐为生，对音乐的不懈探索已经成为我生活的动力。
19. An automatic voltage regulator ensured a constant output from the generator.
    一个自动电压调节器保证了发电机电流输出的稳定。
20. She could hear the constant rhythm of his breathing.
    她能听见他均匀而有节奏的呼吸。
21. Constant wheelchair use will scuff almost any floor surface
    任何地板上经常有轮椅走动几乎都会有所磨损。
22. We had a constant stream of visitors.
    我们这里的游客络绎不绝。
23. The brain requires a constant supply of oxygen
    大脑需要持续供氧。
24. He was arrested after being kept under constant surveillance
    在被连续监视了一段时间后，他被逮捕了。
25. Even the most security-conscious computer user is under constant threat from computer viruses.
    即使是有强烈安全意识的计算机用户也时刻处于计算机病毒入侵的威胁下。
26. She has a low threshold of boredom and needs the constant stimulation of physical activity
    她容易厌倦，需要时常进行活动来刺激一下。
27. Parts of the motor wore out because of constant usage
    发动机的一些部件因为经常使用而磨损了。
28. Constant indulgence in bad habits brought about his ruin.
    经常沉溺于恶习导致了他的毁灭。
29. Constant effort yields sure success.
    功到自然成。
30. Constant vigilance is necessary in order to avoid accidents.
    为了避免意外事故，必须经常保持警惕。

noun

1. a quantity that does not vary

   Synonym:    constant quantityinvariable

2. a number representing a quantity assumed to have a fixed value in a specified mathematical context
   1. the velocity of light is a constant

adj

1. steadfast in purpose or devotion or affection
   1. a man constant in adherence to his ideals
   2. a constant lover
   3. constant as the northern star

2. uninterrupted in time and indefinitely long continuing
   1. the ceaseless thunder of surf
   2. in constant pain
   3. night and day we live with the incessant noise of the city
   4. the never-ending search for happiness
   5. the perpetual struggle to maintain standards in a democracy
   6. man's unceasing warfare with drought and isolation
   7. unremitting demands of hunger

   Synonym:    ceaselessincessantnever-endingperpetualunceasingunremitting

3. unvarying in nature
   1. maintained a constant temperature
   2. principles of unvarying validity

   Synonym:    changelessinvariantunvarying