[ Grammar ]
The Jurassic period is when dinosaurs existed on Earth.
A. Correct as is.
B. Change period into Period.

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Grammar › ViewThe actor and actress (smile/smiles) and (wave/waves) at the crowd.
A. smile and wave
B. smiles and waves
C. smile and waves
D. smiles and wave
Grammar › View
It’s not necessary to go to school on Saturdays.
You ………………to school on Saturdays.
_
A. shouldn’t go
B. have to go
C. mustn’t go
D. don’t have to go
Conjunctions › ViewComplete the sentence: The teacher will call _______ your parents _______ the principal if you misbehave again.
A. either…neither
B. not…or
C. only…if
D. both…and
Grammar › View
He’s in the Navy. He’s a ______.
A. soldier
B. sailor
C. sailorman
D. civilian
