Grammar

Usage:

1. When you come home or back to a place that can be considered your territory (eg. your office) you say ただいま. “I’m home/back.” The addressee’s response is おかえりなさい “welcome back.”
2. もう is frequently used to indicate “already.” When it is combined with a non-past tense, it can mean now. When もうappears in もうそぐ “soon” it forms a softer version of すぐ, “immediately.”
3. たいへん originally meant “big change.” Today it is used to mean that the situation is serious/difficult/awful/etc
4. おやすみなさい, “good night”, is said when you go to bed or part from someone late at night.

Object marker に
A small number of Japanese verbs take に as the object marker. These verbs imply directionality and include verbs corresponding to English (meet, climb, ride).

Past tense (polite) speech
Making a verb polite past tense is changing ~ます to ~ました。The past tense form of ~です is ～でした。The negative of　～ました is ~ませんでした and the negative of ～でした is ～ではありません or ～じゃありませんでした

Verb Conjugation Dictionary フオーム
Japanese verbs have more forms, but less irregularity than in English. The pre-ますフオーム is the most versatile & you hear/see it frequently, but it is useless if you want to look a verb up in the dictionary. Dictionaries use the form that has been considered the most basic in traditional Japanese grammar.

Pre-ますフオーム	Romaji	Dictionary フオーム	Romaji	Glossary
あい（ます）	ai-	あう	au	meet
あり（ます）	ari-	ある	aru	be, exist
いき（ます）	iki-	いく	iku	go
かえり（ます）	kaeri-	かえる	kaeru	go home
かき（ます）	kaki-	かく	kaku	write
きき（ます）	kiki-	きく	kiku	listen, hear
のみ（ます）	nomi-	のむ	nomu	drink
よみ（ます）	yomi-	よむ	yomu	read
い（ます）	i-	いる	iru	be, exist
おき（ます）	oki-	おきる	okiru	get up
み（ます）	mi-	みる	miru	see, watch
おして（ます）	oshite-	おしてる	oshiteru	teach
たべ（ます）	tabe-	たべる	taberu	eat
き（ます）	ki-	くる	kuru	come
ね（ます）	ne-	ねる	neru	go to bed
し（ます）	shi-	する	suru	do

The Pre-ますフオーム ends with either the vowels i or e. When ending with e, add る -ru to make the Dictionary フオーム. These forms are called るーverbs (e-ending.) About 10% of Japanese verbs are this type.

There are two types of verbs whose Pre-ますフオーム ends with i. In one, you need to drop i & add u. These verbs are called うーverbs. Some of the i-ending verbs are るーverbs. In order to create the Dictionary フオーム, you simply add る to the Pre-ますフオーム. About 10% of i-ending verbs are るーverbs. For each i-ending verb, you must remember whether it’s a うーverb or a るーverb.

いらっじゃいます is a うーverb, but it exhibits irregularity here because of a historical change. It was originally pronounced いらっじゃります。 Therefore the Dictionary フオーム is いらっじゃる not いらっじゃう。

The Japanese language only has 2 genuine irregular verbs: きます and Dictionary フオーム’s are くる and する, respectively.