[ Grammar ]
These scientists _____ cultural assimilation in some countries around the world for more than 20 years now.
A. has studied
B. has been studying
C. have studied
D. have been studying
Select your answer:

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Prepositions & Prepositional PhrasesVerbs with Prepositions and ConjunctionsPresent Perfect ContinuousPrepositions of MovementModals in the Past - Speculation and DeductionPresent simple & ContinuousGrammar : Structural Common ErrorsHelping and Linking VerbsRelative ClauseUsed to & would & Past SimpleOther quiz:
Vocabulary and Grammar › ViewChoose the word or phrase that is CLOSEST in meaning to the underlined part in each of the following questions.
Don’t worry about the exam. You only need to do your best.
A. work hard
B. skip the lesson
C. try hard
D. review
Grammar Past and Future Tense › View
Complete the Sentence in the Simple Future:
_____ You call me in the afternoon?
A. Do
B. Did
C. Are
D. Will
