$\begin{array}{|l|l|} \hline \text{up} & \text{an} & \text{and} & \text{useful}& \text{from}& \text{a}& \text{in}& \text{to}\\ \hline \end{array}$

There is a close relationship between man (a)----- nature. Man has established (b)------ friendship with nature. It helps us (c)----- many ways. Similarly trees are closely related (d)------ Trees play (e)------ important role in our life (f)------ economy. Trees are very (g)------ to us. We get oxygen (h)----- them. They are (i)----- great source of food and vitamin. They meet (j)----- our local demands.