I will start with the expression and then give you the tip below.
"to be strapped for cash"
I am strapped for cash = I have no spare money
e.g. A: Can you lend me £5 to get the train home? Sorry, I'd like to help you but I am strapped for cash.
Tip: Think about what grammatical function the whole phrase "strapped for cash" has in a sentence. Is it a verb, noun, adjective, or adverb phrase.
Then think about why these sentences are wrong
"I got strapped for cash"
"My friend was in trouble and strapped me for cash."
"My friend is strapped for cash to catch a train home tonight."
If you feel unsure about how to use the expression, read lots of example sentences!
Another word prevalent in the UK to mean that you don't have much money would be 'skint.' It's quite an informal word.
A: Can you lend us a tenner?
B: Sorry mate, I'm skint at the moment.
Thank you for the tips about how to use idioms.
Here is my sentence with this new idiom.
Last week Richard sold his car. He was strapped for cash and he was in desperate need of money to pay off his debt.
I want just to ask if this idiom gives the say meaning of the expression "I'm broke"
Thanks, Sudeep. Yes, I guess you could use other words which have a similar meaning to "cash". I've only heard "cash", and less commonly "funds".
If you don't hear an idiom spoken, it can be hard to understand how it is used. But if you analyse correctly the grammar and syntax of the idiom itself and the sentences in which you see them, and then practise, you can eventually use them confidently.