[ Grammar ]
John doesn’t know how_________the computer on.
A. to switch
B. switching
C. to switching
D. to have switched

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Tenses, Determiners & Subject Verb AgreementGrammar- Later/LatterModal "Have to"There is or There areComplex PrepositionsModals and PhrasesPresent Continuos TensePresent tense AffirmativePresent Tenses and VocabularyPast Continuous Tense & Past ModalsOther quiz:
Grammar › ViewThere are always regional __________ in every country.
A. differs
B. different
C. differences
Modals › View
You ___________ send text messages when you are driving.
A. haven’t
B. hasn’t
C. should
D. mustn’t