That makes it hard to get a good sense of trends.

VOA: standard.2009.04.28

I think that it makes it hard for that particular area of scientific research to go forward.

我想在这方面的科学研究很难推进。

生物克隆是热点问题 - SpeakingMax英语口语达人

It even, I think, identifies the divine and the human, makes them hard to tell apart;binds them, even while we are being confronted with their difference.

我想，甚至这，使圣与人，难以被分辨，把他们联结在一起，尽管我们也看到,圣与灵之不同。

耶鲁公开课 - 现代诗歌课程节选

"What makes it so rare is that it is highly endangered in the wild, in Sumatra, and it is so hard to get to bloom in cultivation."

VOA: standard.2010.07.30