also: ちゃ · ちゃあ
Expresses a conditional or hypothetical situation, often with a negative or undesirable result. Used after the て-form of verbs and adjectives.
You must not do such a thing.
since ...; if you are going to ...
Indicates that once an action is taken or a state is reached, a certain consequence follows; often used for giving reasons or warnings.
Since it has come to this, it's too late.
one after another; repeated action
Used with verbs to indicate repetition or alternation of actions, often in the pattern 〜ては〜、〜ては〜.
Attaches to the て-form to add emotional emphasis, often in negative commands or strong assertions. Common in casual speech with ちゃ.
Don't cry.
If it rains, the game will be cancelled.
Since you said you'd do it, you have to see it through.
He writes and erases, writes and erases, and just can't seem to finish the letter.
勝手に入っちゃだめ！
Do not go in without permission!
では attaches to nouns and na-adjectives to express a similar conditional idea, whereas ては is used after the て-form of verbs and i-adjectives.
Contracted form common in casual speech; equivalent to ては.
Emphatic or dialectal variant of ちゃ; less common.
Combination of the conjunctive particle て and the topic/contrast particle は. The contracted form ちゃ is a common colloquial reduction.