4-1: The sets of particles with verb

 As I already said, particles have important role in Japanese sentences. This tendency can be understood when they are used with verbs. It is very important point for students to memorize some forms composed of a verb and some particles. You can find typical example in using ‘iku (go)’ and ‘kuru (come)’.
  [Someone] wa [someplace] ni/e ikimasu. (Someone go to someplace.)
As ‘go’ must add ‘to’, Japanese verb ‘iku’ needs ‘ni/e’ to represent the place to go.

 Even if Japanese verbs have some conjugation, it is not difficult so much. Rather you need to learn some forms composed of verb and particles because Japanese sentences are constructed by some particles as pillars of them. You can find like following sentence in a headline in Japanese paper: Nihon no syusyou Amerika he (Japanese Prime Minister go to U.S.). In original Japanese sentence omits ‘iku (go)’ but Japanese people understand its meaning at once. If you regard particles as pillar for Japanese sentences, it will be recognized easily.

 It may be found also in English verb using.
  I apply for my audit of Japanese class to the office.
Compared with other India-European languages, English become near to Japanese. Originally in India-European languages their pillar of sentences is verbs, which show what to affect and what to be affected.
 

4-2: The conjugation of Japanese verbs

 The conjugation of Japanese verbs is very simple and systematic. You need not memorize them like ‘amo’, ‘amas ‘amat’ in Latin. Japanese verbs do not change according to person or the singular/plural but to word after them, that is present/past or positive/denial.

    A I U E O
  I-ku (go)
  Dictionay form I   KU
  Present positive I  KI    + masu
  Past positive I  KI    + masen
  Present negative I  KI    + masen
  Past negative I  KI    + masendesita

  ku-ru (come)
  Dictionay form     KU   RU
  Present positive    KI    + masu
  Past positive    KI    + masen
  Present negative    KI    + masen
  Past negative    KI    + masendesita

  ka-e-ru (return)
  Dictionay form KA-E   RU
  Present positive KAE  RI    + masu
  Past positive KAE  RI    + masen
  Present negative KAE  RI    + masen
  Past negative KAE  RI    + masendesita

As I pointed out the above table, their conjugation is ruled by the changing of some part of their vowel. In the case of masu form, the shifting to ‘I’ rules all their changing. Though Japanese verbs have other kind of changing, they can be understood like this. It shows us the unite composed of vowel and consonant have great role in Japanese grammar.
 

4-3: The difference between present and past tense in Japanese

 Japanese tense is very simple compared with India-Europe languages. It has only two tenses present and past. Then present tense also describes future. But the difference between them are not only this. I consider there is significant difference between Japanese and English. Including English India-European languages decide the tense according to objective series of time. For example, the sentence ‘I forgot that I had said it to her’ has two kinds of tense.

     [Saying this sentence]       [forgot]     [had said to her]
future-----------------+----------------------------+-------------------+------------------past

On the other hand, Japanese does not always concern with the objective series of time.
  A. Pari ni itta toki wa, omiyage wo kau.
  B. Pari ni iku toki wa, omiyage wo kau.
Both sentences means ‘When I go to Paris, I buy souvenir’ and the past tense in A does not reflect the whole tense of this sentence A. The difference between ‘itta’ and ‘iku’ shows the place to buy souvenir. In A the place to buy souvenir is Paris but in B it is his home town.

 I guess it is because Japanese past tense represents subjective memory or image in his mind. When Japanese people use past tense, he regarded something as a decided object that he can remember or image freely. Then he can say it as if it is objective matter. On the other hand, when they use present tense, he regards himself to be in the situation that he says. Then it can represent future tense, too.

 It may be near the sense of the perfect tense in modern European languages. They represent it by ‘have’. That is, ‘I have done’ means ‘I have a experience or situation to do’. Already in German this tense often used to describe past matter: Ich habe das Buch gelesen gestern.
 

4-4: iku/kuru go/come

 When you use Japanese ‘iku(go)’ and ‘kuru(come)’, you must pay attention that the standard point to use these words is different from English. In Japanese this point is where you are now in speaking. Therefore following sentence is unnatural as Japanese, if a American student who lives in Japan say.

 Watashi wa ninenmae Nihon ni ikimashita.
 (I went to Japan two years ago)

He must say ‘Watashi wa ninenmae Nihon ni kimashita. (I came to Japan two years ago) ’, as long as he is in Japan at the moment he says it.

 As in 4-3 pointed out, Japanese is a language to describe something from subjective point of view. This tendency rules all aspects of Japanese. I will refer this point in detail after.