Foil wrapping paper is beautiful but difficult to use.

锡箔包装纸好看却难用。

《柯林斯英汉双解大词典》

Formulas are easy to remember but difficult to use in working out math problems.

公式容易记，但在解决数学问题时却很难应用。

youdao

This is why dentures are comparatively easy to wear, but difficult to use.

这也就是义齿较易戴住，却难于应用的原因。

youdao

But it was often difficult. To protect their towns,the settlers often had to employ people who were expert in the use of firearms.

VOA: special.2010.03.10

A little indirect but not so indirect that is difficult to understand. You should use this often.

有一点委婉，但不至于委婉到让人难以理解。应当尽量多使用这种句型。

Why don't 课堂 - SpeakingMax英语口语达人

When given correctly, it reduces the risk of stroke by 62%, but it is so difficult to use that half of eligible patients are not adequately treated.

FORBES: Replacing Coumadin

But the technology was still difficult to use and there was not space for the wildfire that would come.

FORBES: Age of Context: Social Media Becomes a Mature Platform

Though the U.K. version was printed in broadsheet format for 200 years, it switched to compact size in 2004, making it handier for reading on trains and buses--but more difficult to roll up for use as a fly-swatter.

FORBES: Magazine Article