As he works in a remote area, he visits his parents only _________.

As is known to all language learners, the newly learnt words will soon be forgotten unless they are _______ used in everyday communication.

Although the new road is being used, it has not yet been       opened.

Traffic is bad, ________ in the city center during the rush hours.

 Do you think that bridge               2000 meters long? It doesn’t appear  ______long.