diff --git a/book/en-us/01-intro.md b/book/en-us/01-intro.md
index 0b203dd..03ecd88 100644
--- a/book/en-us/01-intro.md
+++ b/book/en-us/01-intro.md
@@ -43,7 +43,7 @@ Before learning modern C++, let's take a look at the main features that have dep
 
 - **C language style type conversion is deprecated (ie using `(convert_type)`) before variables, and `static_cast`, `reinterpret_cast`, `const_cast` should be used for type conversion.**
 
-- **In particular, some of the C standard libraries that can be used are deprecated in the latest C++17 standard, such as `<ccomplex>`, `<cstdalign>`, `<cstdbool>` and `<ctgmath>` Wait**
+- **In particular, some of the C standard libraries that can be used are deprecated in the latest C++17 standard, such as `<ccomplex>`, `<cstdalign>`, `<cstdbool>` and `<ctgmath>` etc.**
 
 - ... and many more