Fix grammatical error
diff --git a/src/asciidoctor/index.adoc b/src/asciidoctor/index.adoc
index 4ded4de..41239dc 100644
--- a/src/asciidoctor/index.adoc
+++ b/src/asciidoctor/index.adoc
@@ -18,7 +18,7 @@
:toc: left
Log4j Scala API is a https://www.scala-lang.org/[Scala] logging facade based on https://logging.apache.org/log4j/2.x/[Log4j 2].
-Support for Scala versions 2.10, 2.11, and 2.12 are provided, and experimental support for pre-release versions of 2.13 is also provided.
+Support for Scala versions 2.10, 2.11, and 2.12 is provided, and experimental support for pre-release versions of 2.13 is also provided.
Log4j Scala API uses Log4j 2.x as its logging backend by default, but this can also be replaced with compatible libraries (e.g., https://logback.qos.ch/[Logback]).
While this library is not required to use Log4j API in Scala, it does provide idiomatic Scala APIs which are friendlier to use in Scala programs than the Java APIs.
