(2014·日照模拟)For years the government of that country________their responsibility when it comes to the mentally ill

Professor Smith, along with his assistants, _____on the Project day and night to meet the deadline.

spent the whole day repairing the motorbike. The work was ____ simple.

What the scientist said sounded strange, ______, they made sense [ ]

It has been 60 years ______ the two countries established diplomatic ties