The key answer of exercise 9

1. take
2. tell (tell is the only verb here that can be followed by you)
3. talk
4. summarise (+ noun, the main ways / the key points, etc.)
5. giving
6. reviewing (outlining is possible, but more common to review literature – means also you summarise and comment)
7. commenting (the only verb followed by on)
8. outlining (review is possible here, see above, but outline the trends is more likely – both outline and trend refer to a general overview)
9. focus (the only verb followed by on)
10. consider
11. make
12. highlight

The sentences that link together are:

1. a, g, k
2. b, e, i
3. c, h, j
4. d, f, l