77- It is important for every single individual living in this world --------------- hard to protect the environment. 1) to work 2) for working 3) and works 4) that works
\textbf{77-} \quad It is important for every single individual living in this world --------------- hard to protect the environment.
\noindent 1) to work \hspace{1cm} 2) for working \hspace{1cm} 3) and works \hspace{1cm} 4) that works
\noindent