Lie Algebras: a crash course   back  
Basics of Lie algebras: Cartan subalgebra and roots. This should be
explained with the example of SU(2) and SU(3) [1, chapter 8, 12]
                                                                                
Representations of Lie algebras and weights: again this should
be explained mainly with the example of SU(2) and SU(3) 
[1, chaper 11, 12, 13].
                                                                                
Classes of semisimple Lie algebras (Dynkin's classification)
[1, chapter 21].
                                                                                
                                                                                
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[1] W. Fulton, J. Harris, Representation theory, Springer (1991).