Fifty-litre carboy would be the most economical size. Carboys may be retained without charge for two months.
50升的瓶子应是最经济的尺码,这些瓶子可免费保存两个月。
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.
情况很快就弄清了,舞蹈的直线部分是随着太阳位置的变化而变化的。