[ Modal Verbs ]
They ___ solve the puzzle after hours of trying.
A. could
B. were able to
C. should

Random Topics:
Modals and ConditionalsAdjectives vs AdverbsQuestion TagsPassive Voice Active VoiceTo infinitive - GerundPast and Present Continuous tenseArticles and PronounsInfinitive and GerundGrammar and EssayPast with ModalsOther quiz:
Grammar › ViewPeople should use ______ nuclear energy.
A. People should use too many nuclear energy.
B. People should use too much nuclear energy.
C. People should use fewer nuclear energy.
D. People should use less nuclear energy.
Verbs › View
I ________ walk for a long time.
A. Could
B. Walked
C. Canned
D. Was
Future - Will and Be going to › ViewI………………….to the cinema
A. going to
B. will go
C. go
D. am go
Grammar › View
We __________ (live) in the city, but now we live in the countryside.
A. used to
B. uses to
C. didn’t use to
D. did uses
