Sunday, April 15 was a sad day for the linguistics community because this was when Michael Halliday died.
Halliday was known for his grammatical description called Systemic Functional Grammar, or SFG. His theory has been somewhat influential on the study of grammar, as it takes a slightly different approach when compared to other theories.
Michael, you will be missed by me and others in the linguistics community. Your contributions to the field will not be forgotten.