Moreover,saving energy equals saving our natural resources.两save为什么加ing.

Moreover,saving energy equals saving our natural resources.两save为什么加ing.
还有It seems that everywhere there are classes,conferences,workshops and other opportunities offering a piece of paper upon completion to certify that the paper-holder is qualified to do sth.中offering ,
还有In my opinion,attending such class or preparing for the tests.中attending和preparing为甚用ing.
还有This is（ particularly ture in case of） the current labor shortage in many plants.