'A salad asks for a touch of basil.' Should I put an article A before SALAD. Could someone make it clear?

Who can translate this colloquial dialogue into something more understandable. The quote: Chapman rubbed his chin. 'Ainsel,' he said. 'That's not a name. But it'll do at a pinch. What do they call you?' My main concern about a meaning of "But it'll do at a pinch".

How to translate this? A dialogue: - Are they dangerous? - You only get to be my age by assuming the worst. - ....

Is it correctly built sentence? "10 days had gone since your last letter." My concern mostly about using the word 'since' in this phrase.

"A question about a size of the boots" - are the articles correct here? A silly question, but it is always a bit tricky to put an acricle correctly...

"Everything we had done did not work so far." OR "Everything we had done so far did not work." Is one of these phrases correct? Or may be none of them...

Should I use plural or singular noun here? I suppose plural is correct. ".... one of the most useful resources" or "...one of the most useful resource"

Is it a correctly asked question? Will this delayed item come earlier or later or is there an option that it would not be delivered to your warehouse?

Which question is correctly asked? The first o the second one? 1. Do you have an idea when my order could be shipped? 2. Do you have an idea when my order will be dispatched?