The Semi Formal Tone in Business English

If you are writing to a colleague, for instance, a co worker. And it's a co worker you know well, right? So it's sort of bordering on that tone. This is in the middle tween formal and informal. To refer to something as a project, if it's like watering your plants or walking your dog, i ges tis,. Is too informal of a way to refer to that favor totali ye. You would never say that to some one, you know. Yu, say some one, especially if you know them well. Even if it's a neighbor you don't know really well, it's still way too formal.