The snake disappeared from the zoo some time on Thursday. ‘It ____ slipped out of the cage while the door was open.’
A. had to
B. should have
C. needn’t have to
D. must have

Random Topics:
Present Perfect: for/sinceSubject Verb Agreement; Indefinite PronounsVerb + PrepositionNouns and QuantifiersSynonymsSentence Types and ConjunctionsVerb to haveTenses & PrepositionReporting VerbsConditional Sentence Type 3Other quiz:
Present Tense › ViewAnna and Lisa ________________ to school by bus.
A. do not go
B. does not go
C. do not goes
D. does not goes
Subject – Predicate › View
Which sentence contains a compound subject?
A. Living inside the old barn were a large brown horse and a short white cow.
B. Only two dozen children rode the bus that day, but it was still very noisy.
C. The green cicada is an insenct found in yards and parks all over town.
D. A small lizard slithered his way under the rock and out of sight.
A third conditional sentence is used to express something…
A. probable
B. improbable
C. impossible
Grammar ( going to) › View
They are ……………. do sports.
A. go to
B. going to
C. going
