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The fragmentation at the earliest phases is an important process of massive star formation.Investigations of starless cores and prestellar cores are crucial for the origin of stellar initialmass function.However,few samples about the earliest high-mass clumps were investigated.The massive clumps tend to fragment into clusters of stars,where high-mass stars formed.Inthis work,the aims are to explore the habitats of the massive clumps at large scale,andcores/condensations at small scale,and the fragmentation process at different wavelengths.Eight massive precluster clumps(G18.17,G18.21,G23.97N,G23.98,G23.44,G23.97S,G25.38,and G25.71)were selected from SCUBA Massive Pre/Protocluster core Survey(SCAMPS)at850 and 450 μm.VLA D-configuration at 1.3 cm,PbBI BCD configuration at 3.5 and 1.3 mm,APEX at 870 μm observations were followed up,and archival infrared data at 4.5,8.0,24,and70 μm were combined to study the fragmentation and evolution of these eight clumps.The eightclumps at large scale with efficiency radius R = 0.5 pc are compact with high mass ranging from230 to 2300 M☉.They are almost infrared quiet sources with flux S < 15.0 Jy at 24 μm.Mostof their subfragmentations in high spatial resolutions are believed as starless or prestellar coreswithout corresponding infrared emission.Many condensations have high mass larger than 8 M☉ with R = 0.02 pc.Core formation efficiency ranges from 12%to 53%,and the massspectrum index is 0.91 between 4 and 20 M☉ at scale of R = 0.02 pc.Comparison in mass-sizerelation and high-mass star formation threshold indicates that the eight clumps and most of theirsubfragmentations are always massive star-forming candidates.The star formation of these eightclumps may be triggered by UC H II regions nearby.The derived flatter slope of mass spectrummay be indicative a turbulent dominated fragmentation.