My father said that I must work hard.
We worked hard so as to increase our sales.
The authorities are striving in vain to stabilize the currency.
He has been intent on learning French.
He works hard all the year round.
We must work hard to break down social barriers.
She tried hard to clear her mind of doubts.
We thought it wise not to continue our trip.
She was busy doing her hair.
They studied very hard so as not to fail in the exam.