1.
impossible or difficult to perceive by the mind or senses.
感觉不到的或很难觉察的。
2.
To catch sight of(something difficult to discern).
看见，察觉，辨别看到（很难察觉的）东西
3.
an insensible change in temperature.
难以觉察的温度变化
4.
be difficult to detect or grasp by the mind.
难以被心理察觉或领会的。
5.
an imperceptible drop in temperature; ~an imperceptible nod; color is unperceivable to the touch.
难以觉察的气温下降；轻轻的点头；颜色是不能被触觉感觉的。
6.
No man can play the fool so well as the wise man.
智者扮傻瓜，世人难觉察。
7.
Clean: A wine with no noticeable defects; no off-smells or tastes.
干净：没有可察觉的缺点，没有难闻的味道。
8.
And the device is broadcasting a subaudible frequency off any spectrum.
而那些装置在发出一种难以察觉的亚音频声音
9.
In particular, it can be difficult to detect whether a given pair of brackets is part of the inner or outer index.
特别，它可能难于察觉获得的括弧对是内索引或外索引的一部分。
10.
Like the sun, the planets shift their positions so slowly that their day-to-day motion is hard to detect.
象太阳一样，行星的飘移非常缓慢，以致它们每天的运动很难被察觉。
11.
It was a gradual change;so gradual that its beginnings were hardly noticed;
这是一种渐进的变化：因为变得非常慢，所以开始时很难察觉；
12.
Effects of Levodopa on Visual Acuity、Color Perception of Difficult-to-treat Anisometropia Amblyopia;
左旋多巴对难治性屈光参差性弱视视力、色觉治疗效果的观察
13.
The more inward it moves, the more difficult awareness will become.
它进入得越深，要觉察它，变得越加困难。
14.
However the culture is profound and difficult to percept, it is very difficult to measure.
但由于文化深层次的难以察觉性，所以对其进行测度又是相当困难的。
15.
In psychoanalysis, the conscious.
觉察力在精神分析中所指的觉察力
16.
He found it difficult to succeed.
他觉得成功是很难的。
17.
The curved needle of the machine ensures that only a fraction of the main garment is caught, therefore allowing the stitch itself to be almost inconspicuous.
这种机器所使用的弯曲的针保证只勾住了衣服上的一小部分,因此使得线迹本身难以被察觉。
18.
She had some slight gift of observation and that sense, so rich in every woman--intuition. She felt the drag of a lean and narrow life.
她有那么几分观察的天赋和女性特有的直觉。她意识到他们的日子很艰难。