I was looking for some English words which correspond with Japanese ones about this issue:
敬語 - keigo - honorific expression/language
尊敬語 - sonkeigo - respectful language
謙譲語 - kenjougo - humble language
丁寧語 - teineigo - polite language

As I mentioned, keigo has three kinds of honorific language such as sonkeigo (respectful language), kenjougo (humble language) and teineigo (polite language). I'll explain here about them which are regarding JLPT 3 and 4 (I haven't worked on 1 and 2 yet, lol).

Sonkeigo - respectful language
When you don't know well the person or when the person is your teacher, boss and others who are in higher position than you in social life, you use this expression for them directly or indirectly.

At an office. Mr. Kimura is the boss of Miss Katou.
加藤: 木村さん、あの書類はお読みになりましたか？
木村：いや、まだだ。後で読む。


Katou: Kimura-san, ano shorui wa o-yomi ni narimashita ka?
(Kimura-san, did you read the documents?)
Kimura: Iya, mada da. Ato de yomu.
(Not yet. I'll read them later.)

yomu - read
o-yomi ni naru - read as the respectful form
yomareru - read as the respectful form

As you can see, there are two forms about the respectful language. She uses one of them, but can use both of them to Mr. Kimura. And he doesn't use them to her. When Miss Katou says this to her colleague, she doesn't need to use this form. But when she says to someone regarding the conversation between Mr. Kimura, she might use this form because it's used to express respect to him indirectly.

Miss Murata is Miss Katou's colleague.
加藤：　村田さん、あの書類を読みましたか？
村田：　はい、読みましたよ。
加藤：　そうですか。木村さんは、まだお読みになっていないそうです。

Katou: Murata-san, ano shorui o yomimashita ka?
(Murata-san, did you read the documents?)
Murata: Hai, yomimashita yo.
(Yes, I did.)
Katou: Sou desu ka. Kimura-san wa, mada o-yomi ni natte inai sou desu.
(I see. Kimura-san hasn't read them yet, he said.)

The way of formation 1: o-yomi ni naru
o + (masu-form of the verb) + ni naru
yomu - yomi - o-yomi ni naru

But when the verb has one syllable alone in the second group, it doesn't have above form. And even if the verb has two syllables or more, you don't use this form about such a verb when it has a special form for sonkeigo (respectful language). I provide the special verbs once again here just in case:


行く (iku) - いらっしゃる (irassharu) - go
来る (kuru) - いらっしゃる (irassharu) - come
いる (iru) - いらっしゃる (irassharu) - be/exist
食べる (taberu) - 召し上がる (meshiagaru) - eat
飲む (nomu) - 召し上がる (meshiagaru) - drink
寝る (neru) - お休みになる (o-yasumi ni naru) - go to bed // sleep
死ぬ (shinu) - お亡くなりになる (o-nakunari ni naru) - die // pass away
言う (iu) - おっしゃる (ossharu) - say
見る (miru) - ご覧になる (go-ran ni naru) - look/see
着る (kiru) - お召しになる (o-meshi ni naru) - wear
する (suru) - なさる (nasaru) - do
知っている (shitte iru) - ご存知だ (go-zonji da) - know
くれる (kureru) - くださる (kudasaru) - (someone) give (me/us)

The way of formation 2: yomareru
The first group: (nai-form of the verb) + reru
yomu - yoma - yomareru

The second group: (nai-form of the verb) + rareru
oshieru - oshie - oshierareru

The third group:
kuru - korareru
suru - sareru
(They have special forms as well.)

In this form, the exceptional verbs are "dekiru" and "wakaru" and other ones which express potencial meaning. They don't this form.

That's all for this time.

Shizu

Kenjougo - humble language
This language expresses your respect for the listener by making your position lower than the person (namely by using humble expression). This sounds ridiculous, but anyway we use this way so often.

Special verbs for kenjougo:

行く (iku) - 参る (mairu) / 伺う (ukagau) - go
来る (kuru) - 参る (mairu) / 伺う (ukagau) - come
食べる (taberu) - いただく (itadaku) - eat
飲む (nomu) - いただく (itadaku) - drink
言う (iu) - 申す (mousu) / 申し上げる (moushiageru) - say, tell
見る (miru) - 拝見する (haikensuru) - look, see
する (suru) - 致す (itasu) - do
知っている (shitte iru) - 存じている (zonjite iru) - know
あげる (ageru) - 差し上げる (sasiageru) - (I) give
もらう (morau) - いただく (itadaku) - (I) am given (by someone)

At the kitchen. Mr. Hayashi and his wife Eriko are talking.
恵理子：　ねえ、コーヒー飲む？
林：　うん、飲む。

Eriko: Nee, koohii nomu?
(Say, are you going to drink coffee (if I prepare it)?)
Hayashi: Un, nomu.
(Yeah, I'll do.)

The verb's form is quite simple as they don't need to use any keigo. But at the office, Mr. Hayashi uses keigo anyway.

加藤：　林さん、コーヒーお飲みになりますか？
林：　はい、いただきます。
加藤：　木村さんも、お飲みになりますか？
木村：　うん、飲む。

Katou: Hayashi-san, koohii o-nomi ni narimasu ka?
(Hayashi-san, are you going to drink coffee (if I prepare it for you)?)
Hayashi: Hi, itadakimasu.
(Yes, I'll do.)
Katou: Kimura-san mo, o-nomi ni narimasu ka?
(Kimura-san, are you going to do, too?)
Kimura: Un, nomu.
(Yes, I'll do.)

Miss Katou and Mr. Hayashi are colleagues, but not friends. In such a case, normally the conversation is constructed with keigo. In this case, Katou-san uses sonkeigo (o-nomi ni naru), and Hayashi-san does kenjougo (itadaku). Mr. Kimura doesn't use any keigo, and it means that he is rather an arrogant person not only he is in the higher position than two persons. An arrogant person hates to use humble expression needless to say.

as for other verbs, there is a form like "o-machisuru" // "go-shoukaisuru":
o + "masu-form of the verb) + suru
matsu - machi - o-machi suru - wait
go + suru-verb
shoukaisuru - go-shoukaisuru - introduce

But all verbs don't have this form. For example, "untensuru (drive)" isn't used as "go-untensuru". A verb "uru (sell)" is used "o-urisuru", but another one "kau (buy)" isn't used as "o-kaisuru)". As for this verb, we say "kawasete itadaku" as another humble expression, but all verbs don't have this form either. Possibly you might be supposed to learn this case by case. I hope I can make a list for common verbs about this.

See you,
Shizu

teineigo - polite language
Those verbs about this are expressed by masu-form, and you can express your respect to the listener by using such polite language. In kenjougo (humble language), the verb is used with "I/we", but in teineigo (polite language) it doesn't matter of the person for the action.

Hayashi-san visits a company to meet the president at work. He is talking with the secretary.

林：　すみません、社長はいらっしゃいますか？
秘書：　申し訳ありませんが、まだ戻っておりません。お待ちになりますか？
林：　はい、ここで待たせていただきます。

Hayashi: Sumimasen, shachou wa irasshaimasu ka?
(Excuse me, but may I ask you if the president is here?)
Hisho: Moushiwake arimasen ga, mada modotte orimasen. O-machi ni narimasu ka?
(I'm sorry, but he hasn't got back yet. are you going to wait for him (here)?)
Hayashi: Hai, koko de matasete itadakimasu.
(Yes, I wait for him here (if I can).)

In this dialogue, Hayashi-san uses sonkeigo "irasshaimasu ka?" and kenjougo "matasete itadakimasu". And the secretary does sonkeigo "o-machi ni narimasu ka?". And both of them speak in teineigo. If Kimura-san is here instead of Hayashi-san, he will speak in another way:

木村：　社長はいらっしゃるかな？
秘書：　申し訳ありませんが、まだ戻っておりません。お待ちになりますか？
木村：　では、ここで待たせていただこう。

Kimura: Shachou wa irassharu kana.
(I'm wondering if the president is here.)
Hisho: Moushiwake arimasen ga, mada modotte orimasen. O-machi ni narimasu ka?
(I'm sorry, but he hasn't got back yet. are you going to wait for him (here)?)
Kimura: Dewa, koko de matasete itadakou.)
(Then, I'll wait for him here.)

As Kimura-san is arrogant, he is reluctant to use keigo. But anyway he should to do anyway because the president is in the higher position than him, and he needs to do keigo to the president, not the secretary because of that. So, he uses sonkeigo "irassharu" for the president, but he thinks he doesn't need to be polite to the secretary, so he doesn't use masu-form as Hayashi-san said "irasshaimasu ka?".
Also in his second speech to the secretary, he doesn't use masu-form: he just expresses his will with the kenjougo "matasete itadaku". Obviously he doesn't want to use any honorific expressions (keigo), and he is trying to avoid to do as possible he can. But normally we're expected to use keigo, at least teineigo (polite language) when talking to someone who is not your friend or family members, so his behavior like that is rude. Friendlier people might not use teineigo at times, But Kimura-san's speaking way isn't friendly either.

By the way, the secretary says "oru", not "iru/irassharu". Actually there is another form like this about some verbs: teichougo. I'll explain about this and some more next time.

Shizu

丁重後 - teichougo

I was looking for an English expression for this, but I haven't found it yet. Japanese honorific expression (keigo) was divided into three groups mainly so far, and this "teichougo" and one more "bikago" seem to be added (about two years ago) newly. I'm not sure if these newer categories are important for your exams, but anyway they seems to be treated in some textbooks and articles. "Teichougo" means "respectful language" or "polite language" literally, and these two English expression are already adopted for "sonkeigo" and "teineigo" as you know. So, in the meantime I'll just write "teichougo" here.

林：　すみません、社長はいらっしゃいますか？
秘書：　申し訳ありませんが、まだ戻っておりません。お待ちになりますか？
林：　はい、ここで待たせていただきます。

Hayashi: Sumimasen, shachou wa irasshaimasu ka?
(Excuse me, but may I ask you if the president is here?)
Hisho: Moushiwake arimasen ga, mada modotte orimasen. O-machi ni narimasu ka?
(I'm sorry, but he hasn't got back yet. are you going to wait for him (here)?)
Hayashi: Hai, koko de matasete itadakimasu.
(Yes, I wait for him here (if I can).)

Special verbs for teichougo:
行く (iku) - 参る (mairu) - go
来る (kuru) - 参る (mairu) - come
いる (iru) - おる (oru) - be, exist
食べる (taberu) - いただく (itadaku) - eat
飲む (nomu) - いただく (itadaku) - drink
言う (iu) - 申す (mousu) - say
する (suru) - 致す (itasu) - do
知っている (shitte iru) - 存じている (zonjite iru) - know

as you can see in above, some verbs ar also used for kenjougo. But both usages are different.

Well, kenjougo expresses your respect to the listener or the target person (the president, in this case) by making your position lower than the person. For example, Hayashi-san said "matasete itadakimasu", and it gives an impression as if it's pleasure for him to wait for the president, or you might be able to regard it as he want to do if he can, humbly.

But kenjougo is not used if such a target person doesn't exist. For example, when you arrived at the train station, you found the train is late for some reason. But you don't say "kisha o matasete itadakou (I'll wait for the train)": it sounds really funny because you're saying this while making your position lower than the train.

On the other hand, you can use teichougo without any target person. And when you ask when the train will arrive here to someone at the office, he will answer "kisha wa, mamonaku mairimasu (the train will come soon)". In this case, "mairu (come)" is used as teichougo.

Also "oru" is teichougo which means "be/exist", and it's used for human, not object. Teichougo is used by making your or someone's position lower than the listener, and in this dialogue, the secretary uses "oru" for the president to express her respect to Hayashi-san. That means, she makes the president lower than Hayashi-san: guess why? In Japanese, you have to treat someone who is your family members and people in the same working place as the same position as you when you talk to other people. In this case, Hayashi-san is a person in another company, and the secretary has to treat him more politely than people who works at the company where she belongs. If she used sonkeigo "irassharu (be/exist)" for the president to Hayashi-san, it's rude to Hayashi-san because it means that she treated the president more respectfully than Hayashi-san. If someone treats his family more respectfully than his guest, the guest feels uncomfortable? Both situations are alike, I think.

Shizu

Can i just use Teineigo when talking to others (even if there in higer status) or i must know them all x_x...? As for teichougo, it looks like it would be different language, i mean... theres causual and polte what im learning, but + teichougo and kanjougo, its imposible (to me) to learn.

alien-san,

I can understand very well how you're feeling about this, and don't worry, keigo is really difficult even for Japanese as I mentioned before. Especially about the differences among sonkeigo, kenjougo and teichougo, some Japanese people can't distinguish them properly. Honestly, after learning about this issue, I realized that I was wrong about some usages as well, lol.

Well I guess, the most important situation is in business life about using kenjougo, sonkeigo and teichougo. It's really important, and it's one of hard things for fresh businessman, I think. But as for common people... of course you'd better use them more properly, but if you can use at least just teineigo, you can avoid to be a rude person, I think.

We don't use them among friends, so when we have to use them suddenly, that upsets us so often and we use them by mistakes and laugh, lol. So, please don't worry too much unless you'll take exams about this issue or be a businessman in Japan

Shizu