1.
You can't cross the border without valid documentation. It's essential.
没有有效证件你不能过关。这是必要的。
2.
It was imperative to counter this trend.
反击这股思潮是必要的。
3.
It is essential to consolidate the Party and rectify its style of work.
整党整风，这是很必要的。
4.
To attain this aim, inner-Party democracy is essential.
要达到这种目的，党内的民主是必要的。
5.
It is both important and necessary to note this difference.
注意到这个差距是重要的和必要的。
6.
This is not necessary and often not desirable.
这是不必要的，而且经常不符合需要。
7.
This is a necessary part of the process and shouldn’t be short-circuited.
这是这个过程的必要部分，不应该缩短。
8.
It was bound to happen, the abscess had to burst
这是注定要发生的事情，脓肿必定是要出脓的。
9.
This kind of flexible perspective is needed.
采取这种灵活的看法是必要的。
10.
They need not have been punished so severely.
他们受到这样严厉的惩罚是不必要的。
11.
It is essential that the vegetation of this area should be preserved.
保护这一地区的植被是很必要的。
12.
This is essential for our mutual benefit.
这对我们的共同利益是必要的。
13.
It is a correct formula but needs to be given more content.
这个公式是对的，但有加以充实的必要。
14.
So it is necessary for us to explain theoretically the necessity of upholding the people's democratic dictatorship.
理论上讲清楚这个道理是必要的。
15.
This must be in the required data and time format.
这必须是所要求的数据和时间格式。
16.
This desperate expedient, however, was no longer necessary.
当然，这孤注一掷的措施是没有必要了。
17.
The whole caper was unnecessary, in his view.
在他看来，整个这出闹剧都是不必要的。
18.
Do cite the literature, where appropriate.
请务必注明引用文献，这是很重要的。