[ Grammar ]
____ the problem sum many times to his student, Mr Tay gave out a sigh of frustration.
A. Have explained
B. Having explained
C. Have had explained
D. Have been explaining

Random Topics:
ClausesTenses and Verb FormsGrammar (want to/ need to/ have to)Modal "Have to"ConditionalsImperative SentencesAdjectives and PrepositionsNoun PhrasePassive Voice Active VoiceModal SpeculationOther quiz:
Grammar › ViewSara’s family went to the vegetable market, _________ they did not enjoy it.
A. and
B. but
C. or
D. so
Present Perfect Simple and Continuous › View
Marco ______________ sad and angry all day.
A. have seemed
B. has been seeming
C. has seemed
English Morphosyntax › ViewAlex leaves the house after the kids ___________ to school.
A. go
B. gone
C. went
D. didn’t go
Homophones › View
The words “course” and “curse” are homophones.
A. True
B. False
