Add Japanese contrast particle page.

src/Pages/Japan/Japanese/en/contrast-particle.md

@@ -0,0 +1,22 @@
+## は contrast particle
+
+The は particle can be used to indicate contrast.
+
+私<Jps colour="c1" text="は"/>背が低いですが、ケビン<Jps colour="c2" text="は"/>背が高いです。
+
+"I'm short, <Jps colour="c2" text="but"/> Kevin is tall."
+
+The <Jps colour="c1" text="first は particle"/> is the <Jps colour="c1" text="topic marker"/>, the <Jps colour="c2" text="second は particle"/> is the <Jps colour="c2" text="contrast particle"/>.
+
+---
+
+<Jps colour="dim1" text="例文"/>
+
+僕<Jps colour="c1" text="は"/>イカ<Jps colour="c2" text="は"/>すきだけど、タコ<Jps colour="c2" text="は"/>好きじゃない。
+
+"I like squid, <Jps colour="c2" text="but"/> I don't like octopus."
+
+### 関係する動画
+
+* [Episode21 「は」は時々（ときどき）「を」と「が」にとって代（か）わるけど、いつ？ "Wa" sometimes replaces "o" and "ga". When?](https://www.youtube.com/watch?v=8_h0H-V9C4A) by: [Private Japanese Lessons](https://www.youtube.com/@PrivateJapaneseLessons)
+

src/Pages/Japan/en/main.md

@@ -9,4 +9,8 @@ The country of Japan and the Japanese language has facinated me for many years n
 
 These pages contain my notes on learning the language.
 
-* [だけ vs しか](./japanese/dake-vs-shika)
+* [だけ vs しか](./japanese/dake-vs-shika)
+
+#### Particles
+
+* [は contrast particle](./japanese/contrast-particle)

src/Routers.js

@@ -7,7 +7,7 @@ import ElmPage from './Pages/Software/elm/ElmPage';
 
 // Japan
 export const japaneseRoutes = languages.map(lang => {
-    const pages = ['dake-vs-shika',];
+    const pages = ['contrast-particle', 'dake-vs-shika'];
     return pages.map(page => {
       const path = `/${lang}/japan/japanese/${page}`;
       const mdPath = `Japan/Japanese/${lang}/${page}.md`;