LinkedIn – How to Delete Received Recommendations on LinkedIn

To delete a secondary language profile:

Click Profile at the top of your home page.
Click on Edit Profile just below.
Select the language from the Profile dropdown in the upper right.
Click Delete this profile.
Click Yes, Delete Profile.

You can click the "See More" link at the bottom of the Jobs pane which opens up a new page with an expanded list. On that page you can use the faceted filter boxes at the left to narrow the listings. Unfortunately, however, there is no way to permanently save your preferences in this regard.

Note that the "Jobs you may be interested in" feature is still in Beta, and they are actively soliciting feedback (see the link at the bottom of the page), so I recommend clicking that link and making this suggestion.