[ Grammar ]
Other radioactive elements ______ since: actinium (Debierne), radiothorium and mesothorium (Hahn), ionium (Boltwood), etc.
A. were discovered
B. are discovered
C. have been discovered
D. had been discovered
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Quantifiers & Modals of ObligationArticlePhrase and ClauseQuestion Tagand, so, but, becauseso vs suchPassive and Active SentencesWas & Were QuestionsPronouns of QuantityHelping and Linking VerbsOther quiz:
Grammar › ViewRara : That’s right. and then a year later she ____ her manager.
Mona: She look beautiful in your family’s photo.
A. married
B. marry
C. marries
D. getting marry
Grammar › View
Terry is very busy this morning. She’s building something, but her mom and dad _______ know what it is.
A. dont
B. don’t
C. doesn’t
D. didn’t
Present and Past Tenses › ViewI … for two hours before I twisted my ankle.
A. climbed
B. had been climbing
C. had climbed
D. was climbing
General Knowledge › View
Which is the smallest ocean in the world?
A. Atlantic Ocean
B. Gold Ocean
C. English Ocean
D. Tiger Ocean
E. Arctic Ocean