TAKOBOTO

can't / can't afford 〜(doing something)
we can't be relaxing like this drinking tea

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もうすぐしけんなので、あそんでばかりはいられないのです。

Because exam is just around the corner, I can't (afford to) be fooling around.

おきゃくさまがそろそろおつきになってたいへんなので、のんびりおちゃなどのんではいられない

Since the customers will be coming in no time and it will be a hard time, we can't just relaxing around drinking tea.

「〜ていることができない」という可能表現ですが、そこから「〜状態を続けられない」という意味が現れます。
「〜てばかりはいられない」という形は、過度であることを強調する時によく使われます。

one can't afford doing or continue doing a certain action because of nervousnes or to meet the demands of that particular situation or moment. 「〜てばかりはいられない」is almost the same as 「〜てはいられない」, only the ばかり emphasizes of " only just doing .... (action that one should not be doing that moment)".

誠

In #5856, "Since the customers will be coming in no time and it will be a hard time" is awkward. Should read: "Since customers will be arriving in no time and we will have more than our fill..."

bamboo4

Sorry if this is too simplistic, but am wondering if I can use this with the negative form as well?
For example, can I say "___ しなくてはいられない" (Can't afford not to do __)

wribbit

hey wribbit,

If you want to say you cant afford not to do, you should probably use I must do or have to grammar forms. English and Japanese don`t have the same idiomes, so trying to translate your thoughts exactly will end up in strange Japanese. when you want to say Can`t afford not to do try

しなくではいけない (I must)　or しなくではならない (I have to)

also if you want to add a hypothetical if to it
しなければいけない or しなければならない

tigert