Grammar Quiz

[ 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:
If vs. Unless Cleanup vs. Clean UpHomonyms Grammar - much, many, a lot ofPast Continuous and Past Simple TenseDirect Object and Indirect ObjectGrammar (want to/ need to/ have to)Present & Past TensesPerfect Tenses and Vocabulary

Other quiz:

Should / Should not › View

The word should is used to recommend ____________ ideas

A. good

B. bad

C. interesting

D. surprising

Grammar › View

Which of the sentences is a compound sentence?

A. Basketball and soccer are my favorite sports.

B. Valentine’s Day is on February 14th, and St. Patrick’s Day is on March 17th.

How to use : Read the question carefully, then select one of the answers button.