[ Adverbial Clauses ]
When the boss walked into the office, his secretary ________.
A. is typing
B. was typing
C. has been typing
D. typed

Random Topics:
Grammar - Imperatives and LetPast Simple or Past ContinuousSentence CompletionGerund & InfinitiveGrammar: Have toLinking Words and ConjunctionGrammar, Literature, and VocabularyInfinitivesGrammar - Compound SentencesAntonymsOther quiz:
Grammar & Vocabulary › ViewChoose the correct sentence:
A. Artur gets up early on weekdays usually.
B. Artur usually gets up early on weekdays.
C. Usually Artur gets up early on weekdays.
Modals › View
These modals can be used to express possibility.
A. can, could, must
B. will, would, may
C. shall, should, can
D. may, might, could
Vocabulary › ViewWhat might you find in the atmosphere?
A. a house
B. a plane
C. a rock
D. a whale
Grammar › View
Andrea _________her umbrella.
A. has forgotten
B. have forgotten
C. was forgot
D. has forgot