If you are 'out of your depth', you don't have the necessary knowledge, experience or skill to deal with a particular situation or subject.
- When she started talking about quantum physics, I felt completely out of my depth.
- I'm an engineer. I feel out of my depth when we discuss accounting problems.
If you are on 'the crest of a wave', you are being extremely successful or popular. If something is popular, you can try to 'ride (on) the wave'.
- James Blunt is on the crest of the wave in the UK at the moment. You can hear his music everywhere.
- He became successful riding on the wave of using British actors as villains in Hollywood movies.
If you don't get any training before you start a job or activity, you are 'thrown in at the deep end'.
- Everyone was off sick so I was thrown in at the deep end.
- The best way to learn the job is to be thrown in at the deep end.
If you are struggling to spend less than you earn, you are trying to 'keep your head above water'.
- Since they increased my rent, I've been struggling to keep my head above water.
- With the new sponsorship, the team should be able to keep its head above water.
If a company has to stop business because of losses, it 'goes under'.
- The company couldn't afford to pay its suppliers and it went under.
- In this economic climate, a lot of businesses will go under.
If you are in a very difficult situation, you are 'in deep water'.
- If the bank doesn't give us this loan, we could be in deep water.
- He was caught stealing from his company and now he's in deep water.
If you 'make a splash', you get a lot of public attention.
- We need to make a splash by holding a cocktail party for journalists.
- She made quite a splash when she wore such a small dress to the film premiere.
If a noise is 'drowned out' , you cannot hear it because of other noises.
- The sounds of the telephone were drowned out by the noise from upstairs.
- His speech was drowned out by the chanting from the demonstrators.
If you 'test the water', you try to find out what people think about an idea or a situation before you take action.
- Before you decide to sell your house in England and move to Spain, why not go there for a trial three months to test the water?
- This is a big project. We should test the water before making such a large investment.
If a situation is 'sink or swim', it either fails or succeeds.
- Either this works or we are all out of a job. It's sink or swim.
- You'll get no training here. It's sink or swim.
If you 'dive into' something, you do it without really thinking about what you are doing.
- He dived into the project with a lot of enthusiasm but not much thought.
- Let's take our time. There's no point in diving into this without thinking.
If you are 'treading water', you are staying in the same place without making any progress.
- I'm just treading water, waiting for a job with a better salary.
- People lose motivation if they think they are just treading water in their careers.