It may not help you tie your shoe but that little plastic tip keeps the rest of the shoelace, the shoe string from unraveling into weak and useless threads.
它可能不能帮你系鞋带,但那小小的塑料头可以让鞋带的其余部分不会散开成脆弱无用的线。
He bent over to tie his shoe.
他俯身系鞋带。
Suppose you need to pause for some period of time, say to tie your shoe.