火灾蔓延由传导、对流、辐射引起,但它必须通过火灾蔓延的途径去实现。
参考答案:对
用括号内所给词的适当形式完成句子,使句子意思完整,语法正确。
1. These flowers are_________(especial) for our English teachers.
2. The students are_________(confuse) about the_________(confuse) problem.
3. It is sometimes_________(easy) to read books than to do math problems.
4. Our tour guide_________(lead) us to an old temple.
5. The store next to my house is having________(sell).
单颌固定不具备的优点是
A.固定坚实可靠B.便于保持口腔卫生C.可行使张闭口运动D.对进食、语言功能影响较小E.具有一定功能活动,有利于改善局部血液循环