Definition: A replacement or stand-in for something that achieves a similar result or purpose.

Alright class, settle down now, let’s take a look! Today we’re tackling “substitute,” a word quite neat, It means to swap one thing out, a clever feat! The dictionary tells us, with precision true, “A replacement or stand-in, for something you pursue.” Think of it like this: if your cookie's gone astray, You might substitute apples, in a sweet display. Or maybe in math class, when a problem’s too tough, You use a simpler equation – that’s substituting enough! It’s about finding something similar, you see, To do the job for you, effectively and free! So, “substitute” means to trade, to change, to lend, A helping hand, until the very end. Do you have any questions? Let's discuss with glee, Now who can give me an example, just for me?