jackstones造句

• The dam's face is protected by more than a million tons of rock in several layers and more than 180, 000 " jackstones, " ( rebar-reinforced concrete tetrahedrons ), each weighing.
• Andrew Witkin, director of marketing for Mega Brands told Investor's Business Daily that, " They help develop hand-eye coordination, math and science skills and also let kids be creative . " Other toys like Marbles, jackstones, and balls serve similar functions in child development, allowing children to use their minds and bodies to learn about spatial relationships, cause and effect, and a wide range of other skills as well as those mentioned by Mr . Witkin.