The ribosome finds the appropriate amino acid for each "letter" and assembles them head-to-tail in sequence; other "letters" indicate when to start and when to stop.
Adding folic acid to diets costs four or five cents per head per year, with a payback of perhaps 120-fold.
而在食物中添加叶酸仅需每人每年四到五美分，其收益可能达120倍之多。
3
Audi ultra technology has passed an extreme acid test this weekend, ” said head of Motorsport Dr. Wolfgang Ullrich after car #2 crossed the finish line.
当奥迪2号赛车冲过终点线时，奥迪赛车部主管 Wolfgang Ullrich博士说：“本周奥迪极致科技通过了一项极其苛刻的测试。”