fix: use proper definite, and indefinite articles (#378)

src/idioms/pass-var-to-closure.md

@@ -2,12 +2,12 @@
 
 ## Description
 
-By default, closures capture their environment by borrowing. Or you can use
+By default, closures capture their environment by borrowing. Or you can use a
-`move`-closure to move whole environment. However, often you want to move just
+`move`-closure to move the whole environment. However, often you want to move
-some variables to closure, give it copy of some data, pass it by reference, or
+just some variables to the closure, give it a copy of some data, pass by
-perform some other transformation.
+reference, or perform some other transformation.
 
-Use variable rebinding in separate scope for that.
+Use variable rebinding in a separate scope for that.
 
 ## Example
 
@@ -47,13 +47,13 @@ let closure = move || {
 
 ## Advantages
 
-Copied data are grouped together with closure definition, so their purpose is
+Copied data are grouped together with the closure definition, so their purpose
-more clear, and they will be dropped immediately even if they are not consumed
+is more clear, and they will be dropped immediately even if they are not
-by closure.
+consumed by the closure.
 
-Closure uses same variable names as surrounding code whether data are copied or
+The closure uses the same variable names as the surrounding code, whether data
-moved.
+are copied or moved.
 
 ## Disadvantages
 
-Additional indentation of closure body.
+Additional indentation of the closure body.