The sentence "has been fully solved" is correct and usable in written English.
You can use this sentence when you need to refer to a problem that has been completely solved. For example, "The computer issue that had been causing problems for weeks has been fully solved."
Tina Brown from Newsweek felt that while Carey's personal troubles may not have been fully solved, the song made her appear "strong and triumphant".
Although researchers have developed many methods to separate bare ground from other urban features, the problem has not been fully solved due to the similar characteristics possessed by ground and non-ground objects, especially on abrupt surfaces.
The pixelation when moving things that Darrell mentioned in his review hasn't been fully solved.
Since the PTM localization problem has not been fully solved in top-down spectral analysis, we used only the 468 protein-spectrum-matches without PTMs to generate training and test envelope matches.
Since the question of whether hypocholesterolemia is a predisposing factor for GC or a preclinical stage of GC has not been fully solved, our hospital-based case control study aims to overcome this issue by directly looking at the relationship between apoE genotypes and GC as well as their interaction with potential effect modifiers.
Although there have been many results on matrix trace inequality, some important matrix trace inequality problems have not been fully solved.
The treatment/regeneration of bone and cartilage diseases or defects, whether induced by rheumatism, joint dysplasia, trauma, or surgery presents great challenges that have not been fully solved by the current therapies.
However, three inherent hurdles with this potential CO2 capture technology have not been fully solved yet: ammonium bicarbonate solid formation in the absorption tower which may plug the tower packing, high ammonia vapor pressure that results in ammonia slip into the cleaned flue gas, and low CO2 absorption rate resulting in large absorption equipment.
