کلمات change، alter و vary تقریبا هم معنی هستند ولی shift معنی دیگری داره:
"Change" is to make or become different. It could be better or worse.
Ex.: I'm going to change my hairstyle.
"Vary" means to change or cause something to change in amount or level, especially from one occasion to another.
Ex.: My husband varies the vegetables he plants each year.
"Alter" means to change (slightly) the appearance, character, or structure of something, or to be changed in this way.
Ex.: The coat was too long, so I took it back to the store to have it altered.
It was back in 2002 that the shape of the business began to alter.
"Shift" means to (cause something or someone to) move or change from one position or direction to another; (of an idea, opinion, etc.) to change; to move house; to get rid of something unwanted or to sell something.
Ex.:
The wind is expected to shift (to the east) tomorrow.
Media attention has shifted recently onto environmental issues.
Modern detergents will shift most stains.
{Cambridge Dic.}
برای مثال های بیشتر به این لینک ها رجوع کنید:
Change vs Vary - What's the difference? | WikiDiff
What is the difference between alter and change? | WikiDiff