回火稳定是由于合金元素改变碳化物形成温度,并且高温回火时形成的特殊碳化物延迟α相的回复和再结晶,因而使硬度、强度仍保持很高水平。()
参考答案:对
第四部分书面表达(共两节,满分35分)
第一节根据汉语提示填入正确的单词使句子完整(共10小题上,每小题1分,满分10分)。
I began to show interest in American ________(文学) in 1998.
A three-minute silence was held as a mark of _________(尊敬).
Every student who ________ (参加) the lecture given by the hero yesterday must hand in a report.
In order to achieve high ______(成绩), Jack works very hard at all his lessons.
Don’t ________(放弃) English even if you are not interested in it, for it will be helpful to you.
I’m so envious of you getting an __________(额外的) day’s holiday.
We have a new manager. Our ________(以前的) manager quitted his job last week.
The children in that school _________(捐赠)many schoolbags to those in the disaster area.
His latest painting is being ________(展览)at the exhibition.
Much attention should be paid to _________(发展)science and technology.
林木病害流行的因素有哪些?