Sentence examples for a common difficulty is from inspiring English sources

A common difficulty is that men can get an erection but cannot hold it long enough to have sex.

A common difficulty is that the model equations usually have a large number of unknown parameters, such as weights for regulatory interactions, diffusion coefficients, decay and reaction rates, etc. Sometimes, it is feasible to determine the missing parameters experimentally, but in most cases this is difficult or even impossible.

One common difficulty is a stomach filled with gas (Fig. 3).

The most common problem area in switching designs is the inductor, and the most common difficulty is saturation.

But by the time the second paper comes due, the more common difficulty is choosing which of several interesting questions to pursue.

The most common difficulty is how to manage the soft tissues to preserve the blood supply to the cranial segment; releasing incisions make tension-free closure possible so that the segment does not move palatally.

In the management of CKD patients, and particularly of dialysis patients, one common difficulty is the poor correlation between (estimated) K+ intake and serum-K+.

The most common difficulty was inadequate analgesia and the necessity to resite the epidural.

The online forum also made office hours much more efficient: I had very few redundant questions because the common difficulties were usually already addressed on the forum, often within hours of the homework being distributed.

Specifically, students' common difficulties are: students' met-before (previous experience), selecting appropriate representation of the three worlds of mathematical thinking, the transition from one world to another world of mathematical thinking, lack of understanding two different embodiments, and lack of understanding two different symbolic for a concept.

Common difficulties were identified with implementing sentinel systems.