Thunder occurs as ____________ through air, causing the heated air to expand and collide with layers of cooler air.
A. an electrical charge
B. passes an electrical charge
C. the passing of an electrical charge
D. an electrical charge passes

Random Topics:
Conjunctions and PrepositionAdverb or AdjectiveAdjectives and comparisonsComparison & Modal Verbs in Passive VoiceRelative - ConditionalSocial Media VocabularyVerb-ing and InfinitiveCommas and Subordinating ConjunctionsZero ConditionalVerb + InfinitiveOther quiz:
Grammar › ViewWhich sentence is structured correctly? Although it was raining, we went for a walk.
A. We went for a walk although it was raining.
B. Even though it was raining, we decided to stay inside.
C. It was raining, we went for a walk.
D. Although it was raining, we went for a walk.
Tenses › View
Sally is a secretary. She often … a lot of emails at work but right now she … a long letter.
A. writes – is writing
B. is writing – writes
C. write – is writing
D. is writing – write
Grammar › ViewOur boss made us _____ extra hours.
A. to working
B. working
C. work
D. to work
Comma › View
Choose the correct sentence.
A. Swinging the door open quietly the two police officers surprised a young burglar as he worked to disconnect the cable wire from the television set.
B. Swinging the door open quietly, the two police officers surprised a young burglar as he worked; to disconnect the cable wire from the television set.
C. Swinging the door open quietly; the two police officers surprised a young burglar as he worked to disconnect the cable wire from the television set.
D. Swinging the door open quietly, the two police officers surprised a young burglar as he worked to disconnect the cable wire from the television set.
