GIVE ANSWERS - English

”on the job” in British English refers to being at a site which you travel to so that you can perform work required for your employment.

In American English ”on the job” describes the actual performance of the work you were employed and paid for.

So, in British English ”It’s my first week on the job” would mean being at a site where you are performing the work, e.g. at a building site working as a builder away from the building company’s base or a consultant at a client’s offices.

In American English ”It’s my first week on the job” might mean your first week of employment in a factory working there, or in an office doing office work.

”It’s my first week of the job” - the first week of employment, particularly for a new job.

Note that ”the” here is usually used in highly informal and even colloquial spoken language in British and American English. Incidentally, in Australian English, ”the” would be much more commonly used in informal language

Also, be a bit careful how you use the phrase ”on the job”. It can have potentially sexual connotations.