Hi. I'm neither a native speaker, nor a teacher, but I'll respond anyway. I hope you don't mind.
There have been good posts already, so I'll just say a few things:
1. I'd say your teacher is trying to improve your style, not your grammar. I hope she agrees.
2. "gives" vs. "is giving". You say "gives". This makes it a statement of fact. She says "is giving", which makes it the statement of a process. Stylistically, I would agree with your teacher, here. I like "is giving" better, because emphasising the process over the fact implies that you're interested in solving the problem. ("Thailand's giving Chinese tourists a bad impression now, but it won't forever. We're working on the problem.") But, this is a personal preference and I would never change it without explaining why.
3. I think that your teacher changed the meaning of the second sentence.
Information in your sentence:
a) You have made recommendations.
b) They are based on a specific study (mentioned before in the text) by your university.
c) You have provided the recommendations (all of them) with the intention to solve the problems.
Information in your teacher's sentence:
a) You have made recommendations. (Same)
b) They are based on multiple, unspecific studies by your university (two differences: single vs. multiple; specific vs. unspecific)
c) Some of the recommendations provide solutions to the problem (three differences: (1) no longer are all solutions referred to; (2) you are talking about yourself [specifically, your reasons for providing the recommendations; although you delete yourself from the sentence by using the passive voice "the recommendations are provided
by me"], while your teacher talks about the recommendations ["the recommendations provide solutions"] (3) you imply that your recommendations may or may not provide solutions in the future, while your teacher says that some of your recommendations already provided solutions (i.e. they were tried out and they worked) (Notice, how Ruby used present tense, here? ("offer solutions" not "offered solutions")
To me, the two sentences have different meaning. Your teacher's sentence isn't really a version of your sentence; it says something slightly different.