when necessary

Can also be used when necessary, such as PTFE gasket materials.

必要时也可用聚四氟乙烯等材料作垫圈.

The army needs men who are willing to fight, when necessary

军队需要在必要时愿意投入战斗的军人。

Only use your car when absolutely necessary.

非用不可的时候再用你的汽车。

None of us are comfortable with the feeling of being vulnerable, although it seems that the most confident people are those who can allow themselves to be fragile when necessary.

我们谁都不乐意感到自己是脆弱的，可是似乎最自信的人们却是那些有必要的时候让自己脆弱的人们。

This type of exchange between blood centers is a common practice and provides a national pool of blood when necessary.

不同血液中心之间的这种交换是一种惯常的做法，相当于在必要时提供了一个全国性的血库。

Simultaneously, an operative technique of trans-anastomotic duodenal tube and tension suture of fascial space of abdominal wall was applied in 6 cases when necessary.

有6例术中将鼻胃管插入至空肠作为经吻合口的十二指肠支架管，并加作腹壁筋层减张缝合。

One group was asked to seek out an interaction with its waiter; the other, to speak only when necessary ．

一组被要求主动跟服务员互动；另一组只在必要时发言。

The army needs men who are willing to fight, when necessary.

军队需要在必要时愿意投入战斗的军人。

The corroboratory department and its designated expert witness have the right to acquaint themselves with the files of the case requiring corroboration, and question the litigants and witnesses when necessary.

鉴定部门及其指定的鉴定人有权了解进行鉴定所需要的案件材料，必要时可以询问当事人、证人。

They are not afraid to tackle the issues or let the sparks fly when necessary.

他们不怕应对这些问题，也不怕必要时来一番激烈的争论。

When you are on vacation abroad, you can use a smart home controller to switch on or off the electricity when necessary.

在国外度假时，你可以按需使用智能家居控制器来打开或关闭电源。

The magnesium anode rod should be inspected periodically and replaced when necessary to prolong tank life.

应该定期检查阳极棒，为了延长热水器的使用寿命，在必要时，更换阳极棒。

He seems to be making all the arrangements necessary so that he can continue trafficking in drugs when he turns himself in.

他似乎正在做好各种必要安排，以便他自首后还能继续贩毒。

Agricultural labor, of course, traditionally has no time clocks in the fields: the working-day stretches from dawn to dusk when necessary.

传统上，田野中的农业劳动当然是没有上下班概念的：如果有必要，工作时间可以日出而作，日落而息。

The evaluation program developed can communicate with pavement condition database system through DLL ( dynamic link library), perform evaluation of pavement conditions, and conduct overlay when necessary.

本文建立的路面评价系统可以通过动态链接库对状态数据库进行访问，西南交通大学硕士研究生学位论文第Ij页对路面状态进行分析评价，必要时可以进行加铺层的设计。

I'll inform you by mail when necessary.

必要的时候我写信通知你.

Praise them when necessary, but don't lay it on too thick.

必要时要表扬他们，但不能言过其实。

Canals carry the river water to the fields when necessary.

必要时,水渠可以把河水输到田里.

Fire when necessary, but only as a last resort.

必要时可开除，但只是一种最后的手段。

It aimed to get jurisdictions to collect better information and to share it with foreign tax authorities when necessary.

该项目促使各金融管辖区收集更有用的情报，并在必要时分与国外税收机关。

The government, when necessary, has recourse to the armed forces.

政府在必要时可以动用军队。

The state may establish special administrative regions when necessary.

国家在必要时得设立特别行政区。

He reasoned that since the man had a lot of money, as "younger brother" he would be able to use some of it when necessary. Later on, the rich man lost his fortune. The fool no longer called him "big brother".

愚人之所以这样做，是因为这个人很有钱，愚人需要用钱的时候就可以向他借用，所以才称之为“兄长”。

When necessary, instinct is the most reliable resource you can fall back on.

必要时，最保险的办法就是凭直觉判断。

They were narrow enough to travel up rivers and, when necessary, light enough to transport overland.

船身狭窄得足以驶入江河上游, 必要时, 轻盈的船体可以经陆地运输.

The team other teams to focus on learning the advanced training methods and competition experience, and enhance the level of coaches coaching their own teaching experience and, when necessary, to invite foreign coaches to play a good coach.

球队要重视学习其他队伍先进的训练方法和比赛经验，增强教练员自身的执教水平和执教经验，必要时可以邀请优秀的国外教练来担当主教练。

In the circumstance in the foregoing paragraph, the competent authority may order the adoption of necessary response measures and, when necessary, the competent authority may directly adopt handling measures;

前项情形，主管机关得命采取必要之应变措施，必要时，主管机关并得径行采取处理措施；

Ever resourceful, he makes his own clothes when necessary.

他总是足智多谋, 必要时可以替自己缝制衣服.

I told my students my new telephone number so that all of them called me when necessary.

我把新的电话号码告诉了学生，因此，必要时他们都给我打了电话。

With that in mind, be conservative with this method, and only use it when necessary.

认识到这一点，在使用这种方法时，要十分慎重，只有在需要的时候才使用它。