update readme

README.md

@@ -97,7 +97,7 @@ The compiler outputs results in a JSON file. It’s a representation used to bui
         "C:\\Users\\sCrypt\\code\\project\\util.scrypt"
         "C:\\Users\\sCrypt\\code\\project\\contract.scrypt"
   ],
-  "sourceMap": [  //sourceMap, you need to enable sourceMap setting in sCrypt IDE, default is disable.
+  "sourceMap": [  //sourceMap, you need to enable sourceMap setting in sCrypt IDE, default is disabled.
     "0:76:53:76:58",
     ...
   ]
@@ -121,7 +121,7 @@ There are two ways to generate this file (named as `xxx_desc.json`):
       desc: true  // set this flag to be `true` to get the description file output
       asm: true // set this flag to be `true` to get the asm file output
       optimize: false //set this flag to be `true` to get optimized asm opcode
-      sourceMap: true //set this flag to be `true` to get source Map
+      sourceMap: true //set this flag to be `true` to get source map
     }
   );
 ```
@@ -164,7 +164,7 @@ Note that `parameters` in both constructor and function call are mapped to sCryp
 
 In this way, the type of parameters could be checked and potential bugs can be detected before running.
 
-Other complex types are the structure and type aliases of user positioning. They need to be dynamically generated and you can use `buildTypeClasses` to do that.
+Composite types, including structs and type aliases, are dynamically generated by `buildTypeClasses`.
 
 ```typescript
 const {Person, Male, Female} = buildTypeClasses(JSON.parse(descFileContent));