[ Grammar ]
When Marie Curie discovered radium, the elements’ properties and potential were not fully understood.
A. NO CHANGE
B. the elements property’s and potential
C. the element’s properties and potential’s
D. the element’s properties and potential

Random Topics:
Vocabullary TestModals of ObligationAdverb ClauseOffering HelpPast and Past ContinuousModals and ConditionalsZero ConditionalIndependent/Dependent Clauses & Relative ClausesVerb + InfinitiveGrammar: MorphologyOther quiz:
Determiners & Quantifiers › ViewIn_________most social situations,_________ informality is appreciated.
A. the/the
B. a/the
C. X/X
D. a/an
Simple Tenses › View
Which sentence is in Simple Past Tense?
A. She watches TV every evening.
B. He was watching TV now.
C. They watch TV every night.
D. She watched TV yesterday.
Past Simple Vs. Present Perfect › ViewLucy _______ her leg, so she can’t come skiing.
A. Has broken
B. Broke
C. Have broken
Adverbs of Frequency › View
The closest in meaning to rarely is:
A. sometimes
B. seldom
C. frequently
D. never
