题目

当细胞内外存在浓度差时，细胞就会发生质壁分离或复原． 答案：错误 —It’s said that Zhao Benshan as well as Xiao Shenyang flew to ChongQing in his own plane . —Really, When was ________?     —_________ was in April when the closing ceremony of the 2009 Three Gorges International Tourism Festival was held in FuLing, ChongQing. A. that  This                B. this  It       C. it  This              D. that   It