America is lagging behind in the STEM disciplines.
出自-2010年12月閱讀原文
柯林斯高階英漢雙解學(xué)習(xí)詞典釋義
N-UNCOUNT
（覆蓋水管、水箱或屋頂內(nèi)部的）絕熱材料，保溫材料
Lagging is special material which is used to cover pipes, water tanks, or the inside of a roof so that heat does not escape from them or so they do not freeze.
英英詞典釋義
Noun
1. used to wrap around pipes or boilers or laid in attics to prevent loss of heat