A series of attempts() been made he came to a successful solution of the problem.

Our company has been made one of the largest manufacturers in the field of chemical indust

When a decision has finally been made, we obtain a ______ and do a full search of the plac

The contradiction of changes in sea ice coverage at both poles has been made clear by_____

（) has been defined as a "threat of harm made to compel a person to do something

Not the slightest provision has been made for the comfort of the employees, the idea______

Space exploration has been made ______ with the development of modern science and technology.A.it po