工人三轮车
four-stroke cycles───四冲程循环
Krebs urea cycles───癌症尿素循环
Rankine cycles───[热]兰金循环；郎肯循环
menstrual cycles───[生理]月经周期
nitrogen cycles───[土壤]氮循环
oestrous cycles───发情周期
operating cycles───运行周期
water cycles───n.水文循环；水上脚踏车
workmistresses───女工
