Remove the rest English sections and fix some errors.

docs/api/zh/cameras/PerspectiveCamera.html

@@ -133,9 +133,7 @@ scene.add( camera );</code>
 		<p>
 			通过相对于当前[page:PerspectiveCamera.filmGauge .filmGauge]的焦距，设置FOV。
 		<br /><br />
-			默认情况下，焦距是为35mm（全画幅）摄像机而指定的。
-		By default, the focal length is specified for a 35mm (full frame) camera.
-		</p>
+			默认情况下，焦距是为35mm（全画幅）摄像机而指定的。</p>
 
 		<h3>[method:null setViewOffset]( [param:Float fullWidth], [param:Float fullHeight], [param:Float x], [param:Float y], [param:Float width], [param:Float height] )</h3>
 		<p>