Of course, the easiest way to respond to an offer hands and hearts - the standard "Yes" or "no". However, in the first case it will be fairly trivial, and the second shame. But if you want to avoid long explanations and justifications, then this is your option.
If the gentleman you do not like, and with it you are not satisfied and relationships, in language not to be ashamed. All depends on your upbringing. But before you decide to part this way with this man, think again. After this, you're unlikely going to meet and communicate normally.
If the young person you are indifferent but want to maintain friendly relations with him, you need to answer very carefully. One option is to translate the sentence into a joke. But in any case it is not necessary to disparage the man. Just connect your sense of humor. For example, tell him that the more courteous you could not received, so you need to consider, how gallant of you to answer it. So you will win time to come up with a decent answer, and knight its not going to hurt.
Try to refer to external circumstances. Tell me that it is still not ready, you have school, work, vacation only a year (underline). This will help you to delay returning to this issue for a sufficiently long period.
If you still want to respond to the proposal to marry the coveted consent, you still should not hurry. Tell me what you want to think - it just goes to stimulate the interest of men to you. After all, if you don't answer immediately, so not sure of her feelings. And this is a new reason to win you over completely. Wait a day or two and then give your positive response.
You can respond to a marriage proposal quite florid. However, to do so only if you are sure that your partner will appreciate such experiments. For example, you can buy the puzzle and answer the man by a kind of allegory. It may sound like this: "Beloved, I hope our family life will be so much happy days, how many pieces in this puzzle".