Take an exam,

Not give an exam

Ex: The pupil took an exam.
Note: The teacher gives or sets the exam.
The student takes the exam or sits the exam.

To be busy,

Not to have work.

Ex: I’m very busy this morning.

Give an example,

Not bring an example.

Ex: Can you give a better example?

My watch is slow or fast,

Not goes behind or in front.

Ex: My watch is two minutes slow.

 Put on weight,

Not put weight.

Ex: I’ve put on at least three kilos.

Note: The opposite of to put on weight is to lose weight: She has lost five kilos.

It works miracles,

Not it makes miracles.

Ex: That medicine works miracles.