56 Be To + Infinitive: Plans and Arrangements

We use be to + infinitive when we discuss official arrangements, orders or official instructions.

The structure is as follows:
Subject + be to + infinitive + complement.

• The soldiers are to cross the border.
• We are to travel by car from Ankara to Budapest.
• Students are to take the red flag and bring it here.

Sometimes we use be to + infitinive in:

• Sentences that contain definite plans;
• Sentences that contain formal plans.

Moreover, it is also used for formal sentences.