As a studyaid, it is convenient, inexpensive and allknowing.
作为一个学习工具，字典非常方便、便宜而且知识全面。
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I will put a copy of the worksheet in the downloads section in case any of the students have misplaced it, and also because it will be a good studyaid for the upcoming test.
A government study recommended a national highway system of 33,920 miles, and Congress passed the Federal-Aid Highway Act of 1944, which called for strict, centrally-controlled design criteria.