Topics: Modal Verbs
Scientists fear that a patient’s immune system _____ stem cells unless they _____ genetically identical to the patient’s other cells.
A. may reject / are
B. may have rejected / were
C. could reject / had been
D. has rejected / has been
E. would be rejected / were
Select your answer:
Random Topics:
Present Perfect and Present Perfect ContinuousFuture FormsConjunctionCollective NounsFOR & SINCEPossessive Nouns with Apostrophes and PronounsNoun Phrases and AdverbialsGRAMMAR - Could / Could notGrammar - direct/indirect objectsPreposition of PlaceOther quiz:
Modals › ViewIt ________________ rain tomrrow.
A. can
B. must
C. might
Grammar › View
A: Was Tom there when you arrived?
B: No, he ………….
A. had already left.
B. already left.
C. left
D. had been leaving