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The data set are primarily from New Vacuum Solar Telescope[^2] (NVST; [@liu14]) and *Solar Dynamics Observatory*[^3] (*SDO*; [@pes12]). The NVST is a vacuum solar telescope with a 985 mm clear aperture, located at Fuxian Lake, in Yunnan Province, China. It is mainly composed of four instrumentation systems: the adaptive optics system, the polarization analyzer, the imaging system, and the spectrometers. The imaging system has three high-resolution imaging channels for monitoring the photosphere and chromosphere, which include two channels for photosphere in TiO (7058 [Å]{}) and G-band (4300 [Å]{}) and one channel for chromosphere in H[$\alpha$]{} (6562.8 [Å]{}) band. The high-resolution H[$\alpha$]{} images are utilized to study the filament formation process in this paper, and their cadence and spatial resolution are 12 s and $0\farcs163$ per pixel, respectively. The Atmospheric Imaging Assembly [@lem12] and the Helioseismic and Magnetic Imager (HMI; [@sche12]; [@sch12]) on board the *SDO* provide full-disk, multiwavelength, high spatio-temporal resolution observations for this study. The *SDO*/AIA provides seven extreme ultraviolet and three ultraviolet-to-visible channel images with a spatial resolution of 0$\farcs$6 per pixel and a minimum cadence of 12 s, while the *SDO*/HMI provides line-of-sight magnetic fields, continuum intensity, Doppler shift, and vector magnetograms (VMs) on the photosphere 