Our current burdensome tax code is a massive lead weight against the American economy.

现行的税法令人难以负担，就像个沉重的铅块，阻碍了美国经济的发展。

To navigate this river in the old South, a man would stand on the prowess steam ship and bounce a lead weight on a knotted string off the bottom.

很久之前，南方人若要在这条河上航行，必须站在一艘强大的蒸汽船上，用一根打结的绳子把铅块弹离船底。

On the other end, research has shown that lifting light weights where you can perform about 25 or more reps, leads to the greatest levels of muscular endurance development.

另一方面，研究表明，举重可以进行大约 25 次或更多，这样能导致肌肉耐力发展到最大水平。