问题
Have you heard of Earth Day ?—-Yes . The first Earth Day ______ in 1970 to educate us to protect our planet .
A:celebrates
B:celebrated
C:is celebrated
D:was celebrated
B:celebrated
C:is celebrated
D:was celebrated
正确答案是：
同类题型
I have no choice but _____and sleep.
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Do you know why Anna hasn’t come to school today? —I’m not sure. She _______ be ill.
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