小题1:difficulties →difficulty
小题2:Therefore→However
小题3:possible→possibly
小题4:followed→following
小题5:by→after
小题6:has→had
小题7:the two directions →去掉the
小题8:or→and
小题9:that→when
小题10:share∧ us→with
小题1:difficulties →difficulty
小题2:Therefore→However
小题3:possible→possibly
小题4:followed→following
小题5:by→after
小题6:has→had
小题7:the two directions →去掉the
小题8:or→and
小题9:that→when
小题10:share∧ us→with