[ Verb Tenses ]
We _____ the battery when the system short-circuited.
A. were testing
B. had tested
C. had been testing
D. tested

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DescriptionsPast Tense & Present Perfect TenseTAG QuestionsGrammar - Nouns, Verbs, and AdjectivesArticles - rulesPresent Perfect ContinuousPresent Perfect Simple vs ContinuousGrammar and PunctuationComparative AdverbsCommunicative GrammarOther quiz:
Vocabulary › ViewWhat does ‘massive’ mean?
A. That you cannot avoid or prevent
B. larger in size
C. A very bad accident
D. The highest point of something, especially the top of a mountain
Grammar - Wh Questions › View
A: ________ ate my sandwich?
B: Your younger sister.
A. When
B. Where
C. Whose
D. Who
Grammar › ViewWhat change needs to be made? Next summer, Jo climbs a tall mountain.
A. change climbs to climb
B. change climbs to climbed
C. change climbs to will climb
Vocabulary › View
your gullet is located
A. in your chest
B. in your abdomen
C. in your wrist
D. in your mouth
