Tip: See my list of the 
MostThe difference between “intensive” and “intense” is subtle but important. Let’s take a look at the dictionary definitions of their most common meanings:
intense = very strong, extreme
These definitions should help you distinguish between them in most cases. For example, you could say,
because pain can be very strong or extreme, but it can hardly be “involving a lot of activity”. On the other hand, one would say,
because the intended meaning is that “farming involving a lot of activity is responsible for environmental damage”, i.e. there is “too much farming going on”.
We can see the distinction clearly in the following list of the top 10 most commonly used collocations with the two words:
It may be surprising, then, to learn that it is more common to say “intense activity” than “intensive activity”. How is that possible?
“Intense” can also be used when something is strenuous, that is, when it requires a lot of effort. The difference is, as authors of dictionaries like to put it, that intense comes from within, whereas intensive comes from without (from the outside). Intense refers to how you feel about the process; intensive refers to the objective characteristics of the process.
For example, when you say that the workout routine you just did was “intense”, it means that you felt it was hard for you, but someone else could find it easy. On the other hand, if you say that a certain workout routine is “intensive”, it means that it involves a lot of work by design, for everyone.
