实验室中自制洋葱表皮玻片标本时，将标本放置于清水滴中，然后将盖玻片以45°角慢慢压在标本上，这一步骤的主要目的是
Elephants can be ______ years old.
He helped his mother ________ the housework. A. do B. does C.did
Isawaboy_____awaywhenIpassedthepark. A.runB.ranC.for
Itistime_____home. A.goB.togoC.togoto
I get up _____a quarter to six______a hot morning.
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