Minor editing for some docs (#644)

* Edit type.mdx

* Edit primitive-types.mdx

* Edit tuple.mdx

* Update type.mdx

Author: JiaeK

pages/docs/manual/latest/primitive-types.mdx

@@ -156,7 +156,7 @@ ReScript's `true/false` compiles into a JavaScript `true/false`.
 
 32-bits, truncated when necessary. We provide the usual operations on them: `+`, `-`, `*`, `/`, etc. See [Js.Int](api/js/int) for helper functions.
 
-**Be careful when you bind to JavaScript numbers!** Since ReScript integers have a much smaller range than JavaScript numbers, data might get lost when dealing with large numbers. In those cases it’s much safer to bind the numbers as **float**. Be extra mindful of this when binding to JavaScript Dates and their epoch time.
+**Be careful when you bind to JavaScript numbers!** Since ReScript integers have a much smaller range than JavaScript numbers, data might get lost when dealing with large numbers. In those cases, it’s much safer to bind the numbers as **floats**. Be extra mindful of this when binding to JavaScript Dates and their epoch time.
 
 To improve readability, you may place underscores in the middle of numeric literals such as `1_000_000`. Note that underscores can be placed anywhere within a number, not just every three digits.
 

pages/docs/manual/latest/tuple.mdx

@@ -6,7 +6,7 @@ canonical: "/docs/manual/latest/tuple"
 
 # Tuple
 
-Tuples are a ReScript-specific data structure that don't exist in JavaScript. They are:
+Tuples are a ReScript-specific data structure that doesn't exist in JavaScript. They are:
 
 - immutable
 - ordered

pages/docs/manual/latest/type.mdx

@@ -9,7 +9,7 @@ canonical: "/docs/manual/latest/type"
 Types are the highlight of ReScript! They are:
 - **Strong**. A type can't change into another type. In JavaScript, your variable's type might change when the code runs (aka at runtime). E.g. a `number` variable might change into a `string` sometimes. This is an anti-feature; it makes the code much harder to understand when reading or debugging.
 - **Static**. ReScript types are erased after compilation and don't exist at runtime. Never worry about your types dragging down performance. You don't need type info during runtime; we report all the information (especially all the type errors) during compile time. Catch the bugs earlier!
-- **Sound**. This is our biggest differentiator versus many other typed languages that compile to JavaScript. Our type system is guaranteed to **never** be wrong. Most type systems make a guess at the type of a value and show you a type in your editor that's sometime incorrect. We don't do that. We believe that a type system that is sometime incorrect can end up being dangerous due to expectation mismatches.
+- **Sound**. This is our biggest differentiator versus many other typed languages that compile to JavaScript. Our type system is guaranteed to **never** be wrong. Most type systems make a guess at the type of a value and show you a type in your editor that's sometimes incorrect. We don't do that. We believe that a type system that is sometimes incorrect can end up dangerous due to expectation mismatches.
 - **Fast**. Many developers underestimate how much of their project's build time goes into type checking. Our type checker is one of the fastest around.
 - **Inferred**. You don't have to write down the types! ReScript can deduce them from their values. Yes, it might seem magical that we can deduce all of your program's types, without incorrectness, without your manual annotation, and do so quickly. Welcome to ReScript =).