diff --git a/lib/keyboard b/lib/keyboard
index d8629fe83..5b1475c44 100644
--- a/lib/keyboard
+++ b/lib/keyboard
@@ -501,6 +501,8 @@
 222A  cu          ∪	union
 222B  is          ∫	integral
 2234  tf          ∴	therefore
+2235  bc          ∵	because
+2237  ::          ∷	proportion
 2242  -~          ≂	minus tilde
 2243  ~-          ≃	asymptotically equal to
 2244  !~-         ≄	not asymptotically equal to