shrewd
adj
(-er, -est) having or showing good judgement and common sense; astute 有准确判断力和常识的; 精明的; 敏锐的
a shrewd financier, dealer, politician, etc 精明的金融家、 商人、 政治家等
a shrewd argument, plan, measure, investment 高明的论点、 计画、 措施、 投资
make a shrewd guess, ie one that is likely to be right 猜得相当准.
It soon became clear that the straight part of the dance changed when the sun's position changed. If the feeding place was toward the sun, the dancer headed straight upward during the straight part of the wagging dance.