锅炉在开始排污时,首先要()一次阀,然后再慢慢打开二次阀进行排污,在结束排污时,先把二次阀关闭,随后再()一次阀。
参考答案:打开;关闭
读短文,选择正确的单词填空。
Janak and Lily live in India. Yesterday they ____________ (get / got) up early. They ____________
(go / went) to school by school bus. They had computer class, and math. They ____________ (do / did) not
have English class because their English teacher ____________ (is / was) sick yesterday.
Yesterday, Bahati ____________ (get / got) up early, too. She ____________ (help / helped) her mother
first. Then she ____________ (walk / walked) to school. She ____________ (wants / wanted) to eat some
breakfast but she ____________ (has / had) no money.
公安机关遇有( )的紧急情况,公安机关的人民警察依照国家有关规定可以使用武器.
A.拒捕或者其他暴力行为
B.暴乱或越狱或者其他暴力行为
C.逃跑或者其他暴力行为
D.抢夺枪支或者其他暴力行为