[ Vocabulary ]
a process in which one or more substances are converted to one or more different substances
A. conservation of matter
B. closed system
C. chemical reaction
D. reactant

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Too or EnoughTransitional WordsPast Tense (Regular and Irregular)Articles and DemonstrativesPassive and Active VoicePresent Progressive or Present SimpleTenses - Present and PastStative Verbs and TensesAdjectives, Adverbs, and PrepositionsRelative Clauses & Real ConditionalsOther quiz:
Complex Prepositions › ViewEveryone came , _____ Mary. She stayed at home.
A. In face of
B. Out of
C. Except for
Vocabulary › View
A person that teaches.
A. Teacher
B. Student
C. Teach
D. Study
Vocabulary › Viewto ask questions, examine by questioning
A. interrogate
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C. vicious
D. truce
Grammar › View
What are the four principal parts of a verb?
A. Infinitive, present participle, past, past participle
B. Infinitive, present, future, past
C. Present, past, future, past participle
D. Infinitive, present, past, future participle
