Human facial expression recognition is a very important but also difficult subject.

人脸表情识别是模式识别中一个非常重要却十分复杂的课题。

youdao

That's why the English names of Chinese dishes are so long. They are not only difficult to remember but also difficult to read.

这就是为什么中国菜的英文名就都比较长，这种菜名不但难记，而且点起来也绕嘴。

youdao

Its environment control is not only one of the key techniques in modern automatic control but also difficult to control the greenhouse climate.

温室环境调控是现代自控温室中最重要的关键技术之一，温室气候的建模是实现温室控制的关键。

youdao

But it also made it difficult for them to earn enough money to improve their condition.

VOA: special.2010.02.04

Now the intervention studies are stronger methods than the epidemiology studies but they're also more difficult studies to do.

相比传染病学研究,干预性研究更有效,但也更难执行

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

but it's also very difficult.

但是它也很难学。

要继续努力 - SpeakingMax英语口语达人

She was clearly excellent company, but also difficult and prone to quarrels.

ECONOMIST: Titled English writers

If it were easy to become rich we all would be, but as the rich and poor alike know intimately, getting rich is surely glorious, but also very difficult.

FORBES: Rather Than Bash the Rich, We Should Emulate Them

The task of complying with the tax code is now easier (thanks to computers) but also more difficult, because of the code's seemingly organic annual growth in length and obscurity.

ECONOMIST: The costs of complying with America's tax rules