The thing about language when you’re a native speaker is it flies out of your mouth without your having to give it much thought. It’s when you sit down to write that it might give you pause. And sometimes you have to really concentrate on what you intend to convey to determine which words to put on the page.
When you’re not a native speaker and you’re on the receiving end of an oral presentation, your brain is working overtime to translate the onslaught of words coming at you. In this respect, English is fairly unforgiving, and the fact that so many words have double or triple applications or more, depending on context, does little to help you make sense of it all.
The preposition in, for example, has enough applications to fill a small book. Sometimes, it can be interchanged with into. In such instances, whichever one you chose, you’d not only be making yourself understood, but you’d be doing so grammatically. Consider these examples:
Now take a look at these sentences.
Aren’t they saying the same thing? Well, not exactly. The first sentence captures John as he’s already there in the woods, whereas the second is depicting John heading toward the woods. He was on the greens, and now he’s about to enter the forest.