1. “I can't commit to this as I have other priorities at the moment.”
“我无法保证，因为我手头上有其他紧急事情。”
If you are too busy to engage in the request/offer, this will be applicable. This lets the person know your plate is full at the moment, so he/she should hold off[拖延] on this as well as future requests. If it makes it easier, you can also share what you're working on so the person can understand better.
如果你因为太忙而无法答应他人的邀请或提议，你就可以这样说。这能让对方知道你现在有很多事情要处理，因此他/她应该晚点再提出此事以及后续的请求。如果说出来会让事情更简单一些，你还可以与对方谈谈你正在做的事情，以便对方更容易理解。
2. “Now's not a good time as I'm in the middle of something. How about we reconnect at X time?”
“现在恐怕不是好时机，我正忙着一些事情。我们……点再聊如何？”
It's common to get sudden requests for help when you are in the middle of something. This method is a great way to (temporarily) hold off the request. First, you let the person know it's not a good time as you are doing something. Secondly, you make known your desire to help by suggesting another time (at your convenience). This way, the person doesn't feel blown off[（故意）不赴约].
你正忙着某事，却突然接到求助——这种情况再平常不过了。这是（暂时）推延请求的好方法。首先，你让对方知道现在不是好时机，因为你正忙着其他事情。其次，提议另一个（你方便的）时间以表明你愿意帮忙。这样，对方就不会觉得被拒绝了。
3. “I'd love to do this, but…”
“我非常乐意帮忙，可是……”
I often use this as it's a gentle way of breaking no to someone. It's encouraging as it lets the person know you like the idea (of course, only say this if you do like it) and there's nothing wrong with it. It's only because you can't take part due to other reasons such as prior[先前的] commitments or different needs.
我常常使用这种说法，以便温和地拒绝他人。这个方式值得提倡，因为它让对方知道你喜欢这个提议（当然，你得真心喜欢才能这么说），提议本身并没有什么问题，只是出于其他原因（比如早先的承诺或其他需求）才导致你无法参加。
4. “Let me think about it first and I'll get back to you.”
“让我先考虑一下，我晚点给你答复。”
This is more like a “maybe” than a straight out “no.” If you are interested but you don't want to say “yes” just yet, use this. If the person is sincere about the request, he/she will be more than happy to wait a short while. Specify a date/time-range (say, in 1-2 weeks) where the person can expect a reply.
这更像是一个“可能”，而非直接的“不行”。如果你感兴趣，但是不愿意当场应诺，就这么说吧。如果对方真心邀请你，他/她会非常乐意等一会儿。指明一个具体日期或时间范围（比如一到两个星期）给予对方答复。
5. “This doesn't meet my needs now, but I'll be sure to keep you in mind.”
“我现在没有这个需要呢，不过我一定会记在心里的。”
If someone is pitching[推销] a deal/opportunity which isn't what you are looking for, let him/her know straight-out that it doesn't meet your needs. Otherwise, the discussion can drag on longer than it should. It helps as the person knows there's nothing wrong with what he/she is offering, but that you are looking for something else. At the same time, by saying you'll keep him/her in mind, it signals you are open to future opportunities.
如果有人给你介绍一个交易或机会，但它并不是你想要的，你应该直截了当地让他/她知道这不符合你的需求。否则，这个讨论将拖延更长的时间。这能让对方知道他/她所提供的东西没有问题，只是你想要的是其他东西。同时，告诉他/她你会记住这个提议，表明将来有机会的话，你也许会接受提议呢。
6. “I'm not the best person to help on this. Why don't you try X?”
“我不是解决这件事情的最佳人选。何不问问……呢？”
If you are being asked for help with something which you can't contribute much to or don't have
resources for, let it be known they are looking at the wrong person. If possible, refer them to a lead they can follow up on—whether it's someone you know, someone who might know someone else, or even a department. In this way you help steer[引导] the person to the right place.
如果有人求助于你，但你帮不上忙或是没有该方面的资源，你应该让他们知道他们找错人了。如果可以的话，给他们推荐一个能继续跟进的线索——无论是你认识的人，还是某个也许认识这种人选的人，甚至是某个部门。这样你便能将对方指引到正确的位置。
7. “No, I can't.”
“不，我帮不了忙。”
The simplest and most direct way to say no. We build up too many barriers in our mind to saying no. These barriers are often self-created and not true at all. Don't think so much about saying no and just say it outright. You'll be surprised when the reception isn't half as bad as what you imagined it to be.
这是最简单、最直接的拒绝方式。在说“不”的时候，我们在自己的脑中建起了太多障碍。这些障碍常常是自找麻烦，而且与事实不符。不必为说“不”考虑太多。直接说出来吧，你会惊奇地发现对方接受时根本没有你想象的那么糟糕。
Learn to say no to requests that don't meet your needs and once you do that you'll find out how easy it actually is. You'll get more time for yourself, your work, and things that are most important to you. You'll be happy when you start doing it.
学会对不符合自己需求的请求说“不”，一旦学会了拒绝，你就会发现实际上这非常简单。你会得到更多私人时间和工作时间，可以做一些对自己更有意义的事情。学着拒绝，你会变得更加快乐。