ponder
/ˈpɔndə(r); `pɑndɚ/ v[I, Ipr, Tn, Tw]
~ (on/over sth) think about (sth) carefully and for a long time, esp in trying to reach a decision; consider （长时间地仔细）考虑（某事物）（尤指以便作出决定）; 深思
You have pondered long enough; it is time to decide. 你考虑的时间够长的了, 该作决定了.
I pondered (over) the incident, asking myself again and again how it could have happened. 我反覆思考那件事, 一再自问究竟是怎麽回事.
pondering on the meaning of life 深深地思索人生的意义
I am pondering how to respond. 我在琢磨该怎样回答.