The phrase "a major difficulty that" is correct and usable in written English.
It can be used when discussing significant challenges or obstacles in a particular context or situation.
Example: "One major difficulty that we encountered during the project was a lack of resources."
Alternatives: "a significant challenge that" or "a considerable obstacle that".
"I made the mistake of not devoting enough time to the last hour of the game," he writes in that same dissection of the game's pluses and minuses, and outlines the difficulties faced with selling a concept like this to publishers and players alike: "Explaining the concept of an original game with no real prior references is a major difficulty that must not be underestimated".
A major difficulty that affects cancer therapy is the progressive development of drug resistance observed in a subset of patients.
Despite the success of existing algorithms, a major difficulty that has not been sufficiently addressed is that of predicting rare labels.
Although the criterion in (11) is convex, a major difficulty that arises in solving this problem stems from the fact that the function to be minimized is not differentiable.
A major difficulty that all such studies must overcome is the problem of distinguishing effects of genetic variation (e.g., new mutations) from those of nongenetically transmitted variants (Johannes et al. 2009; Roux et al. 2011).
The major difficulty that is faced in extracting ⟨ν⟩∞ by the method of those three studies [ 3, 27, 28] is that it is not possible to directly assay mutants with m mutations, but instead only possible to assay a set of mutants with a distribution of m.
However, these methods for similarity calculation are only at a word or concept level rather than a semantic level, since they measure the similarity merely based on the common words or concepts in the query and sentence, which is the major difficulty that limits the performance improvement for text summarization system.
The notion being developed at that time was that a fundamental difficulty might be that speech needs to be represented as a succession of units, and that acquiring such 'phonological awareness' might be the major difficulty that some children encounter.
There have been two major difficulties that hinder the use of a loudspeaker pipe system as a short-duration acoustic point source generator.
Then one of major difficulties that block the controller design is that the real control signal is hidden in the coupling dynamics between nonaffine system nonlinearity and rate-dependent hysteretic quantizer.
In this respect, administrative bodies in charge of SEA management have issued guidelines and manuals in order to address the major difficulties that hinder SEA implementation in the day-to-day practice.
