Practise what you have read. Use the
simple infinitive (study/work...) or the
perfect infinitive (have studied/have worked...) of the verb in brackets.
KEY TO THE ACTIVITY BELOW
HERE
He must ___________ (study) a lot because he always passes all his exams with brilliant marks.
He must ______________ (study) a lot when he was at school, because his marks were brilliant!
He should _____________(stop) smoking or he is going to end up in hospital.
He should ______________(stop) smoking years ago!
If I had studied more last year, I would ____________(pass) the exam.
If I studied more, I would____________ my next exam.
It is said that he earns a fortune in that company= He is said TO __________(earn) a fortune in that company.
It is believed that he worked for IBM twenty years ago= He is believed TO_____________ (work) for IBM twenty years ago.