# linear algebra – Prove that there is a natural injection \$U otimes V rightarrow E otimes F \$

­­Hello everyone I found the following statement in my lecture :

Let $$U$$ a subset of $$E$$ and $$V$$ a subset of $$F$$ , so there is a natural injection $$U otimes V rightarrow E otimes F$$

But I don’t exactly see why it’s true , and what they mean with natural injection ? Any help would be a lot welcomed thanks in advance.