Corrected some typos

week01/README.md

@@ -190,7 +190,7 @@ int mul(int a, int b)
     return n1 * n2
 }
 ```
-The compilation error messages generated by the prevous source code.
+The compilation error messages generated by the previous source code.
 ```console
 $ g++ -c mul.cpp
 mul.cpp:5:12: error: use of undeclared identifier 'n1'
@@ -206,7 +206,7 @@ mul.cpp:5:19: error: expected ';' after return statement
 3 errors generated.
 ```
 
-If there are compilation errors, it is better to check the source code to make sure all spells are correct, no `;` or `(` missing. For peole in East Asia, they should also be very careful with characters like `；`, `）`, etc. They are different from `;` and `)`. Another Chinese character `　` which is a wider space is easy to be miss used with the normal space.
+If there are compilation errors, it is better to check the source code to make sure all spells are correct, no `;` or `(` missing. For people in East Asia, they should also be very careful with characters like `；`, `）`, etc. They are different from `;` and `)`. Another Chinese character `　` which is a wider space is easy to be miss used with the normal space.
 
 ### Link Errors
 
@@ -215,12 +215,12 @@ Link errors are caused in the link stage. The most common link error is `undefin
 //mul.cpp
 #include "mul.hpp"
 
-int Mul(int a, int b) //mul() is callled in main() but here it is Mul() 
+int Mul(int a, int b) //mul() is called in main() but here it is Mul() 
 {
     return a * b;
 }
 ```
-You will get a link error as follows even you can comile the two files `main.cpp` and `mul.cpp` separately.
+You will get a link error as follows even you can compile the two files `main.cpp` and `mul.cpp` separately.
 ```console
 $ g++ main.o mul.o -o mul
 Undefined symbols for architecture arm64: