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?