Legislative Branch.
立法部门
All federal legislative powers are vested in the Congress of the United States,
所有联邦立法权力都由国会授予的。
which consists of two chambers: a Senate and a House of Representatives. U.S. Const. art. Ⅰ,sec. 1.
根据宪法第一章第一节，国会有两个议院：参议院和众议院。
There are 100 Senators, two from each of the fifty states.
参议院议员有100名，来自50个州，每州2名。
Senators serve six-year terms. U.S. Const. art. Ⅰ,sec. 3, cl. 1, amended by U.S. Const. amend. ⅩⅤⅡ, sec.1.
根据宪法第一章第三节第一款，参议院议员任期6年。
The House of Representatives has 435 members, which are apportioned by population,
根据宪法第一部分第三章节及修正宪法第一部分第10、5、2部分的修正章节，众议院有435名议员，它们按照人口数量分摊，
with each state guaranteed at least one Representative. U.S. Const. art. Ⅰ, sec. 2, cl. 3, amended by U.S. Const. amend. ⅪⅤ, sec. 2.
根据宪法第一章第二节第三款以及修正宪法第二章节的第十四修正款，一个州至少保证一名众议员。
Representatives serve two-year terms. U.S. Const. art. Ⅰ. Sec. 2. cl. 1.
根据宪法第一章第二节第一款，众议院议员任期2年。
The powers of the Congress are specifically enumerated in the Constitution and include, among other thing,
根据宪法第一章第八节第一款，国会的权力都列举在宪法中并且在宪法其它部分包含了各种权力，
the power to lay and collect taxes, duties, and tariffs. U.S. Const. art. Ⅰ, sec. 8, cl. 1.
如设置和征收税收、关税、税则。
Congress also has the power to regulate commerce with foreign nations, among the several states, and with Indian tribes. U.S. Const. art. Ⅰ,sec. 8, cl, 3.
根据宪法第一章第八节第三款，国会也有权力针对与外国的商务、各州之间和印第安部落之间的商务活动制定规定。
This “Commerce Clause" provides the authority for most federal regulation of the environment.
宪法中的“商务条款”为联邦政府由于外部原因制定商务规定提供了权力。