[ Vocabulary ]
easy to use, worldwide system of measurement based on powers of ten. The standards are used by all scientists, and are a modern version of the metric system.
A. SI Standard
B. scientific law
C. observation
D. Metric System
E. English System of measurement

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Future Continuous, Future Perfect and Future Perfect ContinuousAsking for and Giving OpinionLinking Verbs and TensesTenses and StructureHelpful Phrases ModalElectricity VocabularyBe used to vs used toWill vs be going toConjunctive AdverbsOther quiz:
Tenses › ViewMark always (have) _________________ pancakes for breakfast.
A. has
B. had
C. having
D. have
Phrasal Verb › View
Kimmie _____ money yesterday when she wanted to buy some eggs.
A. Ran out of
B. Ran
C. Ran away with
D. Ran into
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A. by
B. with
Grammar › View
Check the underlined clause, is it essential or nonessential?
Chinese schoolchildren learn dances that require difficult body movements.
A. Essential Clause
B. Nonessential Clause
