Well, post some idioms here and we will help you.

Hi dear sir/madam I am an Iranian. I work as a translator and at the moment I am working on children story book. There are some idioms in the book which are really difficult to translate because I dont have any reference to find them.

Only sick can be used attributively, in other words, before a noun: a sick person. In British English, sick is often used to refer to nausea or other rather mild problems with one's health while ill denotes something serious which may require

'past careful' doesn't make any sense as an idiom - but it might make sense in a certain context perhaps. Where did you see it?

Many thanks for your reply and recommendation. It helps a lot. Your list of auxiliaries seems all right, but I would not include used to . I thought it’s just an idiom, but my grammar book and Longman dictionary tell me it’ is

Hi, If you google this idiom + 'origin', you will find various discussions, eg http://wiki.answers.com/Q/What_is_the_Origin_of_the_idiom_Out_of_the_frying_pan_into_the_fire Clive

I find that have to is most often called a semi-modal . It has the effect of a modal like must , but is conjugated like an ordinary verb. ( has to, have to, had to, ... ) I would certainly not call it an auxiliary verb with an infinitive, though

Imagination. This is not the kind of idiom that has an historical origin; it is a catchy image which anyone could dream up.

Hi, There are many, many idioms. Many more than 30. Clive

What in the world are you asking about? Which 30 idioms? They all end with '-elow'??