全部 » Lifestyle » Man » 教师讲解数学公式 Teacher explaining mathematical formulas
这位年轻的老师穿着西装,戴着眼镜,在黑板上解释数学公式,他走近镜头,友好地微笑着。
Young teacher dressed in a suit and glasses, explaining mathematical formulas on a blackboard, as he approaches the shot and smiles friendly.