Wording fix

Author: awtgops

content/guards.md

@@ -1,6 +1,6 @@
 ### Guards
 
-A guard is a class annotated with the `@Injectable()` decorator. Guards should implement the `CanActivate` interface.
+A guard is a class annotated with the `@Injectable()` decorator, which implements the `CanActivate` interface.
 
 <figure><img src="/assets/Guards_1.png" /></figure>
 

content/interceptors.md

@@ -1,6 +1,6 @@
 ### Interceptors
 
-An interceptor is a class annotated with the `@Injectable()` decorator. Interceptors should implement the `NestInterceptor` interface.
+An interceptor is a class annotated with the `@Injectable()` decorator, which implements the `NestInterceptor` interface.
 
 <figure><img src="/assets/Interceptors_1.png" /></figure>
 

content/pipes.md

@@ -1,6 +1,6 @@
 ### Pipes
 
-A pipe is a class annotated with the `@Injectable()` decorator. Pipes should implement the `PipeTransform` interface.
+A pipe is a class annotated with the `@Injectable()` decorator, which implements the `PipeTransform` interface.
 
 <figure>
   <img src="/assets/Pipe_1.png" />