Here are some ways we can give advice or make recommendations: imagine your friend is worried that she is getting unfit. She asks you for some advice. You can respond using one of the following phrases:
You should take some exercise.
You need to take more exercise
You ought to eat more fruit and vegetables.
You shouldn’t eat so much sugary food
Why don’t you go jogging?
How about eating less sugary food?
Use have to or must for stronger advice
You must see a doctor
You have to do some more exercise.
Use imperatives to give advice
Start going to the gym.
Stop drinking so much coke.
Try cycling to work.