[ TOEFL Adjective and Adverb ]
. . . . chief advantage of renewable energy sources is their sustainibilty
A. By the
B. The
C. It is the
D. That the

Random Topics:
like/do not likeAdjectives & PrepositionsAdverbGrammar - Verb FormsIndependent/Dependent Clauses & Relative ClausesComperative and SuperlativeVerb to haveSimple Present Tense vs Present Continuous TenseAdjective / Noun + to InfinitiveConjunctions, Interjections and Sentence TypeOther quiz:
Vocabulary › ViewA root that means: to pull
A. ject
B. port
C. struct
D. tract
Grammar › View
You have … hour to finish your test.
A. the
B. a
C. an
Modal Verbs › ViewHe ___ be Ann’s brother. They look like twins.
A. must
B. may
C. might
D. should
Simple Past Tense › View
She studied Spanish and Greek when she was at university.
A. True
B. False
