联合应用两种药物,其总的作用大于各药单独作用的代数和,这种作用叫做()。
A.增强作用
B.相加作用
C.协同作用
D.互补作用
E.拮抗作用
参考答案:C
根据下列语句画图:
(1)画∠AOB=100°;
(2)在∠AOB的内部画射线OC,使∠BOC=50°;
(3)在∠AOB的外部画射线OD,使∠DOA=40°;
(4)在射线OD上取E点,在射线OA上取F,使∠OEF=90°.
用所给单词的适当形式完成句子。
1. The old man often makes a _ (speak) in our school.
2. The chairman looked _ (ordinary) than we thought.
3. Playing games online is (harm) to your study.
4. Many scientists are trying to explain the (disappear) of the dinosaurs.
5. Although I am your friend, I _ (agree) with your wrong idea.