These two features make shadow detection and removal very challengeable.是什么意思？

These two features make shadow detection and removal very challengeable.

这两个特征使阴影的检测和消除具有相当挑战性.

these

adj. 这些的；pron. 这些；

例句
There's lots of money about these days for schemes like this.
近来这类计划资金充足。

two

n. 两个，两个东西，两点钟，一对；adj. 两个的，我

例句
He has been absent from his desk for two weeks...
他已经有两个星期没有坐在办公桌前了。

features

n. 特征( feature的名词复数 )，特写，[复数]面貌，面貌的一部分（如眼、鼻、口等）；

例句
His name features frequently in the social columns of the tabloid newspapers...
他的名字频繁地出现在各种小报社会专栏的显著位置上。

make

vt. 做，制造，生产，制定，使成为，使产生；vi. 开始，尝试，行进，增大；n. 制造，生产量，性格，形状，样式；

例句
I can't abide people who can't make up their minds...
我受不了优柔寡断的人。

shadow

n. 阴影，影子，鬼，幽灵，隐蔽处；vt. 投阴影于，使朦胧，跟踪，尾随，预示；vi. 渐变，阴沉；adj. 影子内阁的，阴影的，非正式的；

例句
For a moment a shadow seemed to pass across Roy's face.
一瞬间罗伊脸上似乎闪过一丝忧伤。

detection

n. 侦查，察觉，发觉，检查；

例句
...the early detection of breast cancer.
乳腺癌的早期发觉

and

conj. 和，与，而且，于是，然后，因此；

例句
I spend a lot on expensive jewelry and clothing...
我花很多钱购买昂贵的首饰和衣服。

removal

n. 免职，除去，移走，搬迁；

例句
...the removal of benefit from school-leavers...
取消辍学者的补助金

very

adj. 很，非常，恰好是，正是，十足的，特有的；adv. 很，非常，充分，完全；

例句
Most people have very little difficulty in seeing why a Van Gogh is a work of genius.
多数人不难理解为什么凡·高的作品是天才之作。

challengeable

[法] 应回避的，可拒绝的；

例句
Freelancer is toilsome and enjoyable; it is a challengeable occupation full of more feelings of achievement!
自由翻译是辛苦的、也是快乐的; 是具有挑战性的,更是具有成就感的职业!