G $->$ S $$

S $->$ A M

M $->$ S $|$

A $->$ a E $|$ b A A

E $->$ a B $|$ b A $|$

B $->$ b E $|$ a B B

$($a$)$ Describe in English the language that the grammar generates.

$($b$)$ Show a parse tree for the string abaa.