In fact, it is acceptable to fill in the blanks in all capitals in listening comprehension, which can save time and energy in considering this problem.

As for why Keep-fit studio should add hyphens, it belongs to grammatical common sense: keep fit means' keep healthy', which is a verb phrase, such as

If you want to modify a noun, you need to add a hyphen to become a noun:' suitable', and verbs cannot modify nouns.

In addition, the reference answers to health care are also flawed. Actually, studio does not recommend omitting it.