Read the whole sentence first. A body-part idiom usually describes an action, feeling, price, agreement, or memory rather than a real body part. Use it when the listener is likely to know the expression and the register fits the situation.
Say break a leg to wish a performer success before a performance, audition, or similar event: 'Break a leg in your audition tomorrow!' It is a friendly idiom, not a warning or a wish that someone gets hurt. Use good luck when the person or setting may not understand the idiom.
Use break the ice when an action helps strangers or a quiet group begin talking: The host asked a simple question to break the ice. It is usually used for the start of an interaction. If you need to state the action plainly, say introduce yourself, ask a question, or begin the conversation.
British and American English are both standard varieties. Learn common pairs such as colour and color, then follow the spelling and vocabulary style your reader expects.
Notice recurring sound patterns, then listen to the speaker in front of you. Many American accents pronounce r after a vowel, while many southern British accents do not when no vowel follows. Other features, such as t sounds and vowels, also vary within both countries.
Choose the spelling style expected by your reader and keep it consistent. British English often has forms such as colour, centre, and travelled; American English usually has color, center, and traveled.
Use broke as the past simple of break, usually for an action at a finished past time. Use broken as the past participle after have, has, or had, and as an adjective for something damaged or not working. Broke can also mean without money in informal English.
For clear Business English, state the purpose first, give the detail the other person needs, then make the request or next action easy to identify. Use polite direct language and check an agreement when a task has several parts.