Update by review

third_party/ABSEIL_MANUAL.md

@@ -5,17 +5,19 @@ supposed to explain general usage of Abseil.
 
 ## The version of Abseil
 
-gRPC is inteded to use the LTS versions of Abseil only because it simplfies
+gRPC intends to use the LTS versions of Abseil only because it simplifies
 dependency management. Abseil is being distributed via package distribution
 systems such as vcpkg and cocoapods. If gRPC depends on the certain version
-that aren't registered, gRPC in that system wouldn't build or work.
+that aren't registered, gRPC in that system cannot get the right version of
+Abseil when being built, resulting in a build failure.
 Therefore, gRPC will use the LTS version only, preferably the latest one.
 
 ## Libraries that are not ready to use
 
 Most of Abseil libraries are okay to use but there are some exceptions
 because they're not going well yet on some of our test machinaries or
-platforms it supports. Following is targets that are NOT ready to use.
+platforms it supports. The following is a list of targets that are NOT
+ready to use.
 
 - `absl/synchronization:*`: This will be ready from the LTS version in 2021.
 - `absl/random`: [WIP](https://github.com/grpc/grpc/pull/23346).