*get on* (something) [Opposite: get off something]

Definition: to sit on a bicycle, motorbike or horse etc.

(This phrasal verb has more than one meaning)

E.g.1. The bike was too big for him. When he got on it, his feet didn’t touch the ground.
E.g.2. He got on his bike and rode as quickly as he could.

This phrasal verb can’t be separated.

*tag along*

Definition: To follow someone around; or, the person who follows someone around.

Example: 1) You’re going to the new coffee shop? Do you mind if I tag along?
2) My little brother is such a tag along – he follows me everywhere I go!

Etymology: A ‘tag’ is a piece of paper that hangs from something – for example, there is a ‘tag’ on a new pair of pants to tell you how much they cost. ‘Along’ means ‘with’ or ‘beside’. So to ‘tag along’ means to go with somebody but to follow their lead, to ‘hang’ on them as they go about their business.

*knuckle down*

Definition: to begin to work or study very hard, usually after a period of not working or studying.

E.g.1. You’ve had a nice holiday, but now it’s time to knuckle down.
E.g.2. If you don’t knuckle down to some hard work soon, you’ll be out of a job!

This phrasal verb can’t be separated.

*get on*

Definition: to move your body so that you are sitting, standing or lying on something. (opposite: get off)
(this phrasal verb has more than one meaning)

E.g.1. She got on her motorbike and started the engine.
E.g.2. The children got on the bed and started jumping up and down.

This phrasal verb can’t be separated.

*get down*

Definition: to move from a higher position to a lower position.
(this phrasal verb has more than one meaning)

E.g.1. Some people who ride sports bikes try to get their knee down while they are going round corners. They feel that scraping their knee on the road proves that they are good, fast riders.
E.g.2. You shouldn’t be standing on that table! Get down!

This phrasal verb can be separated.