In this talk, the speaker will briefly review the observing modes of wide-field slitless spectroscopy and near-ultraviolet (NUV) imaging, enabled by the cutting-edge instruments on board current space telescopes, i.e. the Hubble Space Telescope (HST) and the James Webb Space Telescope (JWST). He will first introduce the multiple observing programs that acquired deep near-infrared grism and NUV imaging data for which he has been responsible for producing the science-enabling data products, e.g., GLASS, UVCANDELS, MAMMOTH-Grism, and GLASS-JWST. He will focus on two science topics, i.e., 1) the (spatially resolved) chemical evolution of high-redshift galaxies and 2) the constraints on the escape fraction of the ionizing radiation, as two examples of the extragalactic sciences that these unique data sets enable. Finally, the speaker will discuss the prospects for the data to be acquired by the main survey camera of our Chinese Space Station Telescope, which is also designed to specialize on grism spectroscopy and NUV imaging, and talk about how they can benefit from the key experiences on these observing modes.