[ Grammar ]
Burning yard waste releases mold spores, soot, and other contaminants that can aggravate allergies and cause ____ problems.
A. respirator
B. respiration
C. respiratory
D. respired

Random Topics:
Clauses and GerundsSimple Future - WillModal AuxiliaryCorrelative ConjunctionAdjective ending with ED & INGAsking & Giving OpinionPast and Perfect TensesPresent, Past, and Future TimeZero ConditionalSimple Past ContinuosOther quiz:
Vocabulary › ViewThe people despised their king for his cruelty. Despised means:
A. Feel fearful
B. To feel shock at his actions
C. To feel angry at his actions
D. Feel hatred for
Grammar › View
Ray: Where were you born?
Sean: I _____ in Chicago.
A. was born
B. did born
C. born
D. were born
Grammar › ViewMy mother and father ___________ to Australia.
A. have never been
B. has never been
C. has went
D. have went
Paired Conjunction › View
He is …….. intelligent, ……… very funny.
A. not only….but also
B. either……or
C. neither…..nor
D. both…..and
