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

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Grammar › ViewWe always need ____ where they came from and how they did it.
A. to remembering
B. to remember
C. remembering
D. for remembering
Grammar › View
A boy found a wallet on the street ________ he was walking to school.
A. when
B. this time
C. what time
D. while
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
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He’s in the Navy. He’s a ______.
A. soldier
B. sailor
C. sailorman
D. civilian
