The word ‘thing’ can be used in many different ways besides its actual meaning ‘commodity’.
1. Do the right thing : This is a typical way of saying that one has to do what’s right and listen to one’s conscience. When you are confused and can’t decide, you hope to do the right thing, as in, make the correct decision.
2. Sure thing : it is used as an affirmative reply. When your friend invites you over for dinner, to accept the invitation, you may say “sure thing”. You can use this expression to say something is very certain and obvious. So when you are asked what drink you’re going for, you say, “Come on, don’t you know beer is a sure thing for me?”
3. The real thing : to say something whose authenticity can’t be disputed or to bring out a fact or something hidden, you may say, “The real thing is that the company needs to cut costs.”
4. Sort of thing : it’s a casual way of commenting on something that someone talks or asks you about. “Why don’t we do a parachute jump?” “Sorry, I’m not into that sort of thing.”
5. The nicest thing: it is generally used by girls when they are generously complimented or gifted something extremely precious. “That’s the nice thing anyone has ever said/given me.”
6. The next big thing: When you’re talking about a breakthrough in science or technology, you can describe it as ‘the next big thing’. Cloud computing is the next big thing. When a new actor has given a few hit films and you want to say he’s here to stay, you say, “He’s the next big thing.”
7. In the thick of things: a way of saying you’re extremely busy or you’re caught up with something that is keeping you too occupied. So when your friend gives you a call to chat about something and you’re extremely busy, you say, “Sorry, I’ll call you later on, I’m in the thick of things.”
8. First thing in the morning : to say something has to be done on priority basis or you promise someone to do something on priority basis. An electronic store employee tells his customer, “My technician is coming to your house first thing in the morning.”
9. It’s a thing of the past : you can use this phrase to refer to traditions people don’t observe any more, or when talking about outdated things in general. Analogue phones are a thing of the past.