Japanese Te Form Explained
Introduction - What is The 'Te' Form?
The 'Te' form is a special form for verbs in the Japanese language in which the verb in question is conjugated to end with the hiragana て, hence the designation 'Te' form. To get the most out of this guide, I recommend that you have some ability to read Hiragana.
Japanese Verb Groups
In case you are unfamiliar, there are three distinct verb groups in the Japanese language. Group one contains all verbs which do not end in る, except for the two irregular verbs as well quite a few verbs which end in る however do not follow the group two conjugation pattern. Group two contains all verbs which end in る and are conjugated by simply dropping the る ending. Group three contains the two irregular verbs する (suru - to do) and 来る (kuru - to come).
Verb Group One Conjugation Rules
To conjugate a Japanese group one verb into its respective て form, you need to choose a specific stem change which based on the verb's ending:
If the verb ends with う, つ or る; replace the ending with って
If the verb ends with ぶ, む or ぬ; replace the ending with んで
If the verb ends with く or ぐ replace the endings with いて and いで respectively.
If the verb ends with す; replace the ending with して
買う (kau) - (to buy)
立つ (tatsu) - (to stand)
走る (hashiru) - (to run)
遊ぶ (asobu) - (to play)
読む (yomu) - (to read)
死ぬ (shinu) - (to die)
Group One Exception Notice
There verb 行く (iku - to go) is an exception verb when it comes to its て form. Rather than taking the ending 行いて, it instead takes 行って as if it ended in る, つ or う. On a side note, verbs which end in ぬ are extremely rare.
Verb Group Two Conjugation Rules
Group Two Verbs (also called the Ichidan verbs) are much simpler, all you need to do is drop the る ending and replace it with て in all cases.
たべる - To Eat
ねる - To Sleep
しんじる - To Believe
Group Three Conjugation
Easy, there are only two irregular verbs and する arguably is not even irregular here.
Negative て Form
The negative て form is formed by taking the plain negative form of a verb and then ending it with the hiragana で (de).
働く - (hataraku) - 働かない - (hatarakanai) - 働かないで - (hatarakanaide)
読む - (yomu) - 読まない - (yomanai) - 読まないで - (yomanaide)
寝る - (neru) - 寝ない - (nenai) - 寝ないで - (nenaide)
The Te form is used as the basis for a variety of different suffixes and auxiliary verb pairings which stem from the verb in the て form itself. On its own however, the て form is used as a conjunction to pair multiple verbs into a single sentence, and can be translated to 'and' exclusively with verbs.
今日は勉強して働きました (kyou wa benkyoushite hatarakimashita) - (I studied and worked today.)
The て form on its own is also used as a more informal command or imperative form:
早く手伝って。！ - (hayaku tetsudatte) - (Help me quick!)
When paired with the suffix ください the verb becomes a polite command:
ゆっくり食べてください。 - (yukkuri tabete kudasai) - (Please eat slowly).
ちょっと早く働いてください。 (cyotto hayaku hataraite kudasai) - (Please work a little bit faster.)
Using the negative て form will turn it into an negative command:
彼に聞かないでください。 (kare ni kikanaide kudasai) - (Please do not ask him).
When the て form is paired with the verb いる the verb will become present progressive, indicating that the action is taking place right now, or the action is habitual and takes place repeatedly.
兄は晩御飯を作っています。 (ani wa bangohan wo tskutteimasu) - (My older brother is making lunch.)
父は毎日働いています。 (chichi wa mainichi hataraiteimasu) - (My father works every day.)
The ところ (tokoro) form is essentially an extension of the present progressive, and it translates to "in the process of doing" something.
料理をしているところです。 (ryouri wo shiteiru tokoro desu) - (I am cooking now -/- I am in the process of cooking.)
When a verb in the て form paired with から (kara) - (often translating to 'because or from), it translates to after the action:
朝ごはんを食べてから学校へ行きました。 (asagohan wo tabete kara gakkou e ikimashita) - (After I ate breakfast, I went to school.)
When a verb in the て form is paired with the verb あげる (ageru) - (to give), the verb then translates into an action that was performed for or in the interest of someone else:
木村さんに問題の詳細を説明してあげました。(Kimura san ni mondai no syousai wo setsumei shite agemashita) - (I explained the details of the problem to Mr. Kimura.)
When paired with ほしい, a meaning of necessity is expressed.
この自転車を直してほしいんです - (kono jitensya wo naoshite hosiindeus) - (I need you to repair this bicycle.)