ては・
An "if" that expects trouble: if that happens, or if things stay like this, it will be no good. てはいけない, "must not", is this "if" with "no good" after it. Without the trouble, ては is "again and again", often said twice (～ては～ては).
if you do that
If we give up here, all our effort so far will go to waste.
in conversation
If you rush like that, it'll only be more dangerous.
if this goes on
If we keep waiting here like this, we won't make the last train.
How to form it
Verb in the て-form + は
帰って → 帰っては, 急いで → 急いでは. Also 暑くては, and では after a noun or a な-adjective: 外食では, 複雑では.
In conversation
ては → ちゃ では → じゃ
帰っちゃ, 急いじゃ, そんな態度じゃ.
Something that goes on
Verb ている → ていては
待っている → 待っていては.
- Before it
- Usually something already happening or just proposed, often with そんなに, こんなに, このまま or ここで.
- After it
- The trouble: 困る, 危ない, 間に合わない, something that can't be done.
- Where you'll meet it
- The full form in writing and careful speech; ちゃ and じゃ with family and friends.
In use
If you leave without saying anything, everyone will worry.
In heat like this, I can't bring myself to do anything.
If you eat out every day, you will spend too much on food.
With that attitude, the discussion won't get anywhere.
That won't do.
Word for word: "if it's like that, I'm in trouble".
Two things to know
Good news doesn't follow it
What follows ては is nearly always a problem, so a good result sounds wrong. A plain "if" is たら or ば.
Not said: この
(If you take this medicine, you'll soon be better.)
The everyday exception is a suggestion: てはどうですか, a more formal たらどうですか.
Why not talk it over with your teacher?
ていては: if this goes on
With ている, the thing is going on now, or is a habit. The trouble comes if it doesn't stop.
If you keep staying up this late every night, you won't be able to concentrate in morning class.
If you keep repeating the same mistake, you will lose people's trust.
Close neighbours
The rule "must not", from a teacher's てはいけません to ちゃだめ at home. なくてはいけない, "if you don't, it's no good", is "have to".
Bicycles must not be parked here.
～ては～てはN2
One thing, then another, over and over. No trouble comes into it.
Since this morning the weather has kept going from sunny to cloudy and back again.
では・じゃあN5
Alone at the start of a sentence, では is "well then".
Everyone is here. Well then, let's begin.
たらN4
The everyday "if", for good news and bad. In conversation a warning is often just たら.
If you take this medicine, you'll soon be better.
Check yourself
1Which one fits?
毎日
Choose an answer to see why.
2What is this person saying?
そんなに
Choose an answer to see why.
More detail
In conversation ていては shrinks to てちゃ.
You can't stay in bed forever.
More sentences
If the rain keeps falling like this, there is a risk that the river will overflow.
With the person in charge away, it is hard to decide anything here and now.
If we keep putting the problem off, it will never be resolved.
If you keep cutting back on sleep to work, you'll ruin your health sooner or later.
If you keep holding back that much, you won't get your point across.