difference between carry out, perform, execute, and implement

implement - хэрэгжүүлэх, нэвтрүүлэх
implement something 
to make something that has been officially decided start to happen or be used
---synonym carry out
to implement changes / decisions / policies (бодлого)/ reform(өөрчлөлт, шинэчлэл)

perform - биелүүлэх, гүйцэтгэх (санамж: зөвхөн эдгээр зүйлийг биелүүлнэ гэж хэлэхэд ашиглана - work, task, duty)1. perform something    to do something, such as a piece of work, task, or duty (үүрэг)    ----synonym carry out    to perform an experiment / a miracle (гайхамшиг) /  a ceremony (ёслолын арга        хэмжээ)

• A computer can perform many task at once

2. perform something    entertain an audience by playing a piece of music, acting in a play, etc    to perform somersaults (хий эргэлт) / magic tricks

•     the play was first performed in 2007

execute - гүйцэтгэх 1. execute someone (for something)    to kill someone, especially as a legal punishment

• He was executed for treason

2. execute something    (formal) to do a piece of work, perform a duty

• the crime was cleverly executed.
• check that the computer has executed your commands

3. execute something    (formal) to successfully perform a skillful action or movement

• the pilot executed a perfect landing

carry out - биелүүлэх (санамж: зөвхөн хэлсэн зүйл болон асуугдсан зүйлийг хийхэд ашиглана)carry comething out or carry out something1. to do something that you have said you will do or have been asked to do    to carry out a promise / a threat / a plan /  an order
2. to do and complete a task

• Extensive tests have been carried out on the patient.

what's the difference between carry out/conduct/execute/implement/perform?

• While many of these are similar in form, here are some situations where one might be better than another... 
  
  carry out - to follow orders that someone has given you, to follow through with plans you set for yourself, to finish something you started (it's also what you do with dinner you order and pick up from a restaurant!)
  
  execute - to put a plan into effect, usually something with some importance or finality (execute the landing sequence to land the plane at the end of a flight, execute the self-distruct function on a machine). This is where the meaning "to kill" is connected - to execute someone is to plan to put a finish to their life, and then to do it. Similarly, you use execute for wills - when you die, an executor executes your will, or does the things you said should be done in your will. 
  
  implement - to use something such as an item or a plan or program
  
  perform - do do a certain task, sometimes doing it while being observed and/or judged; you perform tasks at work, but you wouldn't "perform" an errand to go grocery shopping
  
  So, to put them all into one short story: Yesterday, I carried out a plan I have to solve world hunger. I started by conducting an experiment in my lab at work. I executed each stage of the experiment perfectly, and came up with the answer! If we implement my results all over the world, no one will go hungry again! If my co-workers and I continue to perform well, we might even get a raise!
  
  Hope that helps with some of the nuances in these words!

• In practical terms, they are all the same. In most cases you can use any that you want. Some of these terms have alternate meaning. Execute can mean to kill. Implement can be a noun meanings some used to do something like a pencil is a writing implement