[ Grammar ]
_______is necessary for the development of strong bones and teeth.
A. It is calcium
B. That calcium
C. Calcium
D. Although calcium

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Verbal and Appositive PhrasesPrepositionWorld Literature VocabularyModal and Phrasal VerbsTenses and PronounsLinking WordsUncountable NounsModals for DeductionRelative PronounGrammar - Collective NounsOther quiz:
Grammar › ViewHe had been working for more than 11 hours. He __________ be tired after such hard work.
A. mustn´t
B. should
C. must
D. have to
Homonyms › View
The tree had one large ___ that looked strong enough to hold a swing.
a. bough
b. bow
“Open a can of worms” means….
A. share information that complicates the situation
B. getting ready to go fishing
C. openings up a can with stinky food
D. having a difficult time
Grammar › View
That smells good! What ________
A. do you cooking?
B. are you cooking?
C. do you cook?