[skip ci]Update typo in query boolean expr md (#11164)

Signed-off-by: Nyanliang567 <yanliang.qiao@zilliz.com>

docs/design_docs/query_boolean_expr.md

@@ -74,13 +74,13 @@ Tips:
 1. NIL represents an empty string, which means there is no Predicate for Expr.
 2. Gramma is described by EBNF syntax，expressions that may be omitted or repeated are represented through curly braces `{...}`.
 
-After syntax analysis, following rules will be applied:
+After syntax analysis, the following rules will be applied:
 
 1. non-vector column must exist in Schema.
 2. CompareExpr/TermExpr requires operand type matching.
 3. CompareExpr between non-vector columns of different types is available
 4. The modulo operation requires all operands to be integers.
-5. Integer columns can only match integer operands. But float columns can match both integer and float operands.
+5. Integer columns can only match integer operands. While float columns can match both integer and float operands.
 6. In BinaryOp, the `and`/`&&` operator has higher priority than the `or`/`||` operator
 
 example：