be triggered by the magnetic reconnection between the emerging flux and the pre-existing magnetic flux [@yok95; @shi98; @cheu14; @li17].

![The material injection process of the filament and the evolution of photospheric magnetic fields. (a1)-(a4) and (b1)-(b2) H$\alpha$ images at different moments observed by NVST. The black arrow and the blue one indicate two filamentary structures in the panel (b1), respectively. (c1)-(c4) and (d1)-(d4) The corresponding line-of-sight field from $SDO$/HMI. The yellow box in the panel (d1) and the gray box in the panel (b1) show the same region for calculating negative flux and intensities of $SDO$/AIA seven bands.\[fig2\]](figure2.eps){width="\columnwidth"}

The jets and material supply for the filament {#sec3.2}
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The cool material began to be lifted by a small jet (H$\alpha$ jet) to filament height at about 05:09 UT. Fig.\[fig3\] (a) and (b) show this material injection event in H$\alpha$ images observed by the NVST. At 05:09:34 UT, we find a brightening occurred in the vicinity of the south-western footpoint of the filament marked by the blue arrow in the panel (a), and the material began to be injected from the chromosphere to higher atmosphere. The panel (b) shows that the cool plasma was directly injected into the filament and the 