Use language appropriate to register and level of formality
(i) Select from and use a range of lexical phrases which are appropriate for both formal and informal situations
Let's borrow your pen a minute.
Do you think you could lend me your pen? I'll only be a minute.
(ii) Know ways in which spoken language may vary, according to the situation and/or the relationship between speakers, and adapt learner's own speech to suit the situation
More use of vague language in informal speech.
Tendency to string simple sentences together in informal speech.
Ellipsis is more common in informal speech.
Speakers may mix registers, such as switching between social and business registers, or between formal and informal language.
For more information please see element Lr/L2.2b