简述温室土壤防止积盐危害的措施。
参考答案：
1）科学施肥；
2）灌水洗盐；
3）生物除盐；
4）换土除盐；
5）改进灌水技术和减少蒸发。
When he learned that his brother had returned from abroad, he set off to his home _____. Which of the
following is not OK? [ ]
A. immediately
B. right away
C. right then
D. right now
E. at once
发电机强励值是多少？
