必须的

In my capacity as spy I had to take care to maintain my cover, and it was therefore necessary to appear to participate.

在我身为间谍时，我不得不小心保护我的食死徒身份，参与那些活动也是必须的。

This is most necessary to present the proper take-off of the horse to remain in good balance.

这是保证马有正确的起跳，保持平衡，最必须的条件。

Many had a renewed interest in natural theology and stressed the importance of social change.

许多了新的兴趣自然神学，并强调必须的社会变革。

Writing this blog I realized how ridiculous I have been looking these last few days.

法庭和教堂是两个你永远盛装去的地方，这应该是必须的。

This herb will also assist in opening the heart to the 1000-petal lotus, as this movement is also required for a healthy immune system and thymus gland in ascension.

该草本也将协助心脏打开到1000瓣莲花，因为这一运动对一个健康的免疫系统和胸腺也是必须的。

What i mean in this 'laugh' is titter, not simply 'laugh at'.

关于你的第一点，介词on 不是必须的，因为在口语中，this morning 完全可以表达这个意思。

To make a good photo tripod is a must.

要成为一名优秀的照片三脚架是必须的。

It can create a UI if it chooses, but it doesn't need to.

它能够根据你的需要创建用户界面，当然了这不是必须的。

Even unexceptional photos can be transformed into various stunning masterpieces.

提供了所有必须的绘图工具和功能，使你能轻松得到独特而专业的艺术效果。

Many different colors, in themselves raw and unsightly, are required in order to weave the harmonious pattern.

所以顶不悦目的黑色和灰色也是必须的；有了它们，才可以使你的图画美丽。

The reasons of iron ions content overproof in grade Ⅱ desalting water system,such as variation water quality,contamination of regenerant , operation adjustment of pretreatment system and switching operation of bed were discussed.

对二级脱盐水系统中铁离子含量超标的原因，如来水水质发生波动、再生剂受到污染、预处理系统操作调整、床体运行切换等进行了论述。

You were hired to drum up new business, so go and do it.

公司雇你招徕新业务，你就做你的事好了。