diff --git a/futures/src/executor/async_std.rs b/futures/src/executor/async_std.rs
index 641dfbd2..27949e31 100644
--- a/futures/src/executor/async_std.rs
+++ b/futures/src/executor/async_std.rs
@@ -2,7 +2,7 @@ use crate::Executor;
 
 use futures::Future;
 
-/// A type representing the `async-std` runtime.
+/// An `async-std` runtime.
 #[derive(Debug)]
 pub struct AsyncStd;
 
diff --git a/futures/src/executor/thread_pool.rs b/futures/src/executor/thread_pool.rs
index 09cb4d21..1ec5bf69 100644
--- a/futures/src/executor/thread_pool.rs
+++ b/futures/src/executor/thread_pool.rs
@@ -2,7 +2,7 @@ use crate::Executor;
 
 use futures::Future;
 
-/// A thread pool for futures.
+/// A thread pool runtime for futures.
 pub type ThreadPool = futures::executor::ThreadPool;
 
 impl Executor for futures::executor::ThreadPool {
diff --git a/futures/src/executor/tokio.rs b/futures/src/executor/tokio.rs
index 4c609686..20802ceb 100644
--- a/futures/src/executor/tokio.rs
+++ b/futures/src/executor/tokio.rs
@@ -2,7 +2,7 @@ use crate::Executor;
 
 use futures::Future;
 
-/// The `tokio` runtime.
+/// A `tokio` runtime.
 pub type Tokio = tokio::runtime::Runtime;
 
 impl Executor for Tokio {
diff --git a/futures/src/executor/wasm_bindgen.rs b/futures/src/executor/wasm_bindgen.rs
index 2a12a1c0..69b7c7e2 100644
--- a/futures/src/executor/wasm_bindgen.rs
+++ b/futures/src/executor/wasm_bindgen.rs
@@ -1,6 +1,6 @@
 use crate::Executor;
 
-/// A type representing a `wasm-bindgen-futures` runtime.
+/// A `wasm-bindgen-futures` runtime.
 #[derive(Debug)]
 pub struct WasmBindgen;