1119 is you bi paper (essay) marked to gce-o-levels standard..........it's an attempt at international benchmarking of english standards........mostly ignored by unis, although some will accept a good grade in lieu of ielts/toefl.........

obviously somebody who is getting a1 in 1119 will also get a1 in spm.........

but some a1's in spm will actually be a2 or b3 in 1119......

generally, for lower grades, expect to get 1-3 grades lower in 1119 compared to spm.......