[ 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

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Places in TownPresent Perfect Simple & Present Perfect ContinuousAdjectives (-ed / -ing)Passive Voice - Present Simple and Past SimpleVocabulary and Sentence StructurePrepositions and Phrasal VerbsNoun, Adjective, and Adverb ClausesCommon Grammar Mistakes and Spelling TipsVerb + InfinitiveArticles & QuantifiersOther quiz:
Sentence Adverbs & Third Conditional › ViewComplete the third conditional sentence: ‘If Noah ________ (study) harder, he could have passed the exam.’
A. study
B. studied
C. had studied
D. have studied
Perfect Verb Tenses › View
Identify the perfect tense in the following sentence: “I have never seen such a beautiful sunset.”
A. Present Perfect
B. Past Perfect
C. Future Perfect
D. Simple Present
Passive Sentence › View“What a beautiful dress you’re wearing!”
“Thank you. It_____ especially for me by a French tailor”.
A. is made
B. has made
C. made
D. Was made
Grammar › View
Mrs. Benbow ___________ her friend a tea from Starbucks!
A. gave
B. gived
C. gives
