He is working as an agent for the Central Intelligence Agency.

As the phrase 'If it does not sing, let's wait until the cuckoo sings' suggests, we should wait patiently until the opportunity comes.

He has done everything he can to prepare for the exam, and now he is in a state of 'doing all that is humanly possible and waiting for fate to take its course'.

The National Aeronautics and Space Administration announced a new space exploration plan.

The National Aeronautics and Space Administration announced a new space exploration plan.