ВОЙДИТЕ, ЧТОБЫ НАЧАТЬ ОБУЧЕНИЕ С АУДИО-ЗАПИСЬЮ

Nai uchi ni ないうちに
Note that this phrase includes a negative form in Japanese, but becomes an affirmative expression in English translation.

1. After the stem of nai-form of verb

暗くならないうちに帰りましょう。
Kuraku naranai uchi ni kaerimashou.
Let's go home before it gets dark .

忘れないうちに彼女に電話しておこう。
Wasurenai uchi ni kanojo ni denwa shite okou.
I'll call her before I forget.

-> see also: mae ni, uchi ni
 
nakereba ikenai なければいけない
Predicative phrase (expressing obligation imposed by the speaker) meaning: (you) must.
Nakereba is the ba-form of the negative adjective nai. It may be replaced with nakutewa, nai to, or the informal nakya.

1. After the stem of nai-form of verb

もっと勉強しなければいけません。
Motto benkyou shinakereba ikemasen.
You must study harder.

「私も行かなければいけませんか。」「いいえ、結構です。」
''Watashi mo ikanakereba ikemasen ka.''Iie, kekkou desu.''
''Do I have to go, too?'' ''No, you don't need to.''

2. After ku-form of adjective

もっと軽くなければいけません。
Motto karuku nakereba ikemasen.
It needs to be lighter.

3. After (adjectival) noun + de

老人に親切でなければいけません。
Roujin ni shinsetsu de nakereba ikemasen.
You must be kind to old people.

-> See also: nakereba naranai, nakutemo yoi
 
nakereba naranai なければならない
Predicative phrase (expressing obligation/necessity of the speaker) meaning: have to.
Nakereba may be replaced with nakutewa or the informal nakya.

1. After the stem of nai-form of verb

九時までに会社に行かなければなりません。
Ku ji made ni kaisha ni ikanakereba narimasen.
I have to go to the company by nine o'clock.

もっと単語を覚えなければなりません。
Motto tango o oboenakereba narimasen.
I have to learn more words.

2. After ku-form of adjective

アパートは駅にもっと近くなければならない。
Apaato wa eki ni motto chikaku nakereba naranai.
The apartment house needs to be much closer to the station.

3. After (adjectival) noun + de

話は論理的でなければならない。
Hanashi wa ronriteki de nakereba naranai.
The speech needs to be logical.

-> See also: nakereba ikenai, nakutemo yoi, neba naranai
 
Nan なん
Interrogative adjective meaning: what, how many, several, a few, many.
Nan is a euphonically changed form of nani and is used to modify a noun.

1. Followed by counter

「今何時ですか。」「二時十五分です。」
''Ima nan ji desu ka.'' ''Ni ji juu go fun desu.''
''What time is it now?'' ''It's two fifteen.''

「終わるまで何分かかりますか。」「半時間です。」
''Owaru made nan pun kakarimasu ka.'' ''Han jikan desu.''
''How many minutes will it take to finish it?'' ''Half an hour.''

外国に何回行ったことがありますか。
Gaikoku ni nan kai itta koto ga arimasu ka.
How many times have you been abroad?

2. Followed by counter + ka

やっと何人か来ました。
Yatto nan nin ka kimashita.
Some people have finally come.

ジェーンは何日か前に会いました。
Jeen ni wa nan nichi ka mae ni aimashita.
I saw Jane a few days ago.

3. Followed by (number+) counter + mo

私は何十冊も本を買いました。
Watashi wa nan jussatsu mo hon o kaimashita.
I bought dozens of books.

外国語を覚えるのに何年もかかります。
Gaikokugo o oboeru no ni nan nen mo kakarimasu.
It takes many years to master a foreign language.

4. Followed by no + noun

なんの音楽が好きですか。
Nan no ongaku ga suki desu ka.
What (kind of) music do you like?

-> See also: nani