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This paper reports the findings of a study examining classroom questioning behavior and its impacts on students' development. A triangulation was conducted to collect data: observations of nine university English lessons, semi-structured interviews with six teachers and focus group discussions with three groups of students. The data showed that many of the questions asked were lower cognitive questions and that they were mostly answered in chorus or by teacher nomination. The findings revealed that questioning was employed by the teachers to check text comprehension, hold the students' attention on the texts, to enhance and protect teacher's and students' face, to maintain classroom discipline, to establish teacher authority, and to gain student respect and acceptance. The results indicate that the questioning behavior identified is likely to have potential negative impact on the students. Tentative suggestions are made for improving questioning style to fit the Chinese educational reform agenda.

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Despite significant advances in the development of highly efficient and robust oxygen evolution reaction (OER) electrocatalysts to replace noble-metal catalysts, commercializing OER catalysts with high catalytic activity for sustainable development still remains a great challenge. Especially, transition-metal Fe-based OER catalysts, despite their earth-abundant, cost-efficient, and environmentally benign superiorities over Co-and Ni-based materials, have received relatively insufficient attention because of their poor apparent OER activities. Herein, by rational design, we report Ni-modified pyrite (FeS 2 ) spheres with yolk−shell structure that could serve as pre-electrocatalyst precursors to induce a highly active nickel−iron oxyhydroxide via in situ electrochemical topological transformation under the OER process. Notably, as confirmed by the results of X-ray absorption spectroscopy, X-ray photoelectron spectroscopy, and density functional theory (DFT) calculations, Ni doping could effectively regulate the intrinsic electronic structure of FeS 2 to realize a semiconductor-to-semimetal transition, which endows FeS 2 with dramatically improved conductivity and water adsorption ability, providing prequisites for subsequent topological transformation. Moreover, systematic post-characterizations further reveal that the optimal Ni-FeS 2 -0.5 sample completely converts to amorphous Nidoped FeOOH via an in situ electrochemical transformation with yolk−shell structure well-preserved under the OER conditions. The electronic structure modulation combined with electrochemical topotactic transformation strategies well stimulate the reactive Fe sites in Ni-FeS 2 -0.5, which show impressively low overpotentials of 250 and 326 mV to drive the current densities (j) of 10 and 100 mA cm −2 , respectively, and a Tafel slope as small as 34 mV dec −1 for the OER process. When assembled as a water electrolyzer for the overall water splitting, Ni-FeS 2 -0.5 can display a low voltage of 1.55 V to drive a current density of 10 mA cm −2 , outperforming most of the transition-metal-based bifunctional electrocatalysts to date. This work may provide new insight into the rational design of other high-performance Fe-based OER electrocatalysts and inspire the exploration of cost-effective, ecofriendly electrocatalysts to meet the demand for future sustainable development.

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