1. have difficulty (in) doing something
结构：主语 + have/has + difficulty + (in) + 动名词
注意：介词 in 可省略，动词需用动名词形式（-ing）。
例句：
I have difficulty understanding his accent.
（我很难听懂他的口音。）
She has difficulty finishing her homework on time.
（她很难按时完成作业。）
2. find it difficult to do something
结构：主语 + find + it + difficult + 不定式
强调主观上觉得困难。
例句：
He finds it difficult to wake up early.
（他觉得早起很困难。）
They find it difficult to adapt to the new environment.
（他们觉得适应新环境很难。）
3. have trouble (with) doing something
结构：主语 + have/has + trouble + (with) + 动名词/名词
例句：
She has trouble remembering names.
（她记名字有困难。）
We have trouble with solving this math problem.
（我们解这道数学题有困难。）
4. struggle with something
结构：主语 + struggle (with) + 名词/动名词
强调“费力、挣扎”去做某事。
例句：
He struggles with speaking in public.
（他当众讲话很吃力。）
The students struggled to complete the project.
（学生们费了很大劲才完成项目。）
5. It's hard (for someone) to do something
结构：It's + hard + (for someone) + 不定式
说明客观或主观上的困难。
例句：
It's hard for me to focus in a noisy room.
（在吵闹的房间里我很难集中注意力。）
It's hard to imagine life without the internet.
（很难想象没有互联网的生活。）
其他同义表达：
face challenges (in) doing something
（面临做某事的挑战）
We face challenges in balancing work and life.
run into problems (with) doing something
（遇到做某事的困难）
They ran into problems installing the software.
语法注意：
difficulty 是不可数名词，不能说 difficulties（除非指具体的多个难题）。
have trouble 和 have difficulty 用法类似，但更口语化。
struggle 可接 with + 名词，或直接接不定式（struggle to do）。
希望这些表达对你有帮助！
