A perplexing feature of insomnia is that people seem to overestimate their sleep loss. Rita L. Atkinson et al.
Chronic acalculous biliary disorders are among the most perplexing diagnostic and therapeutic challenges in medicine. Richard M. Gore
A perplexing problem, often encountered by cat owners, is that of a refusal to use the litterbox after using it for years in the past. Susan L. Mathews
perplexinglyadverb
a perplexingly complex problem
This was all that I could observe of her in the dim light and under the perplexingly strange circumstances of our meeting. Wilkie Collins