docs: fix grammar and spelling
MODIFY
doc/guides/gc-arena-howto.md
doc/guides/gc-arena-howto.md
@@ -14,7 +14,7 @@ GC (garbage collector) must ensure that object is "alive", in other
words, that it is referenced by somewhere from the program. This can be
determined by checking if the object can be directly or indirectly
referenced by root. The local variables, global variables and
-constants etc are root.
+constants etc. are root.
If program execution is performed inside mruby VM, there is nothing to
worry about because GC can access all roots owned by the VM.
@@ -65,7 +65,7 @@ objects (See `MRB_GC_FIXED_ARENA` and `MRB_GC_ARENA_SIZE` in
doc/guides/mrbconf.md).
If you create many objects in C functions, memory usage will increase, since
-GC never kick in. This memory usage may look like memory leak, but will also
+GC never kicks in. This memory usage may look like memory leaks, but will also
make execution slower as more memory will need to be allocated.
With the build time configuration, you can limit the maximum size of

MODIFY
doc/guides/mrbgems.md
doc/guides/mrbgems.md
@@ -111,7 +111,7 @@ conf.gembox 'custom'
This will cause the `custom` GemBox to be read in during the build process,
adding `mruby-time` and `mrbgems-example` to the build.
-If you want, you can put GemBox outside of mruby directory. In that case you must
+If you want, you can put GemBox outside the mruby directory. In that case you must
specify an absolute path like below.
```ruby

MODIFY
doc/mruby3.0.md
doc/mruby3.0.md
@@ -75,7 +75,7 @@ to be default `mrb_value` representation. Now the default is
## `MRB_WORD_BOXING`
Pack `mrb_value` in an `intptr_t` integer. Consumes less
-memory compared to `MRB_NO_BOXING` especially on 32 bit
+memory compared to `MRB_NO_BOXING` especially on 32-bit
platforms. `Fixnum` size is 31 bits so some integer values
does not fit in `Fixnum` integers.
@@ -116,7 +116,7 @@ Instructions that access pool[i]/syms[i] where i>255.
* `OP_STRING16`
* `OP_LOADSYM16`
-Instructions that load a 32 bit integer.
+Instructions that load a 32-bit integer.
* `OP_LOADI32`

MODIFY
doc/mruby3.1.md
doc/mruby3.1.md
@@ -119,7 +119,7 @@ If the size of `mrb_float` and `mrb_int` are same, the last 2 bits in the `mrb_f
Previous NaN boxing packs values in NaN representation, but pointer retrievals are far more frequent than floating point number references. So we add constant offset to NaN representation to clear higher bits of pointer representation. This representation is called "Favor Pointer" NaN Boxing.
-Also, previous NaN boxing limit the size of `mrb_int` to 4 bytes (32 bits) to fit in NaN values. Now we allocates integer values in the heap, if the value does not fit in the 32 bit range, just like we did in Word Boxing.
+Also, previous NaN boxing limit the size of `mrb_int` to 4 bytes (32 bits) to fit in NaN values. Now we allocate integer values in the heap, if the value does not fit in the 32 bit range, just like we did in Word Boxing.
## Constant Folding

docs: fix grammar and spelling