Republicans have also splintered into myriad factions, making them hard to herd.
European campaigns are usually dominated by local and national concerns, making them hard to read.
Often, necessary details are scattered across a computer hard drive, making them hard to find.
Euro notes have a series of intricate watermarks and holograms, making them hard to copy.
But trying to create giant rogue waves in a laboratory tank is very difficult, making them hard to study.
However, the palps of dead males are fixed in an inflated state, making them hard to remove.
Their solid-fuel propellant allows them to be launched at short notice, making them hard to detect and neutralise.
Several of the 10 kinds he planted were russets, which have matte brown skin, making them hard to market.
On a more practical note, there are various training programmes available, but many cost money, making them hard to access.
Old-school baby-proofers like me used plastic covers because they plugged tightly into outlets, making them hard for babies to remove.
Such discussions, the internet-era equivalent of the journal club, have hitherto been strewn across the web, making them hard to find, navigate and follow.
