Update exploit-protection-reference.md

Author: denisebmsft

defender-endpoint/exploit-protection-reference.md

@@ -313,7 +313,7 @@ If you attempt to set the instruction pointer to a memory address not marked as
 
 ### Compatibility considerations
 
-All x64, ARM, and ARM-64 executables have DEP enabled by default, and it can't be disabled. Since an application has never been executed without DEP, compatibility is assumed.
+All x64, ARM, and ARM-64 executables have DEP enabled by default, and it can't be disabled. Since an application isn't executed without DEP, compatibility is assumed.
 
 All x86 (32-bit) binaries have DEP enabled by default, but DEP can be disabled per process. Some old legacy applications, typically applications developed prior to Windows XP SP2, might not be compatible with DEP. Such applications typically generate code dynamically (for example, JIT compiling) or link to older libraries (such as older versions of ATL) which dynamically generate code.