Question

To get to the central bus station, you have to _____ at the traffic lights then follow the road.

Answer 1

To get to the central bus station, you have to turn right at the traffic lights then follow the road.

It is a simple instructional sentence which emphasizes on what has to be done towards the bus station. We can write turn right or turn left, whatever we want to, since no options are given.

Answer 2

Right or left 
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To get to the central bus station, you have to Right/ left at the traffic lights then follow the road.

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In this sentence, the words should be right or left. Because in this sentence the direction of the bus station is not given and if it is not given then the answer in the  blanks should be Direction