用括号内所给单词的适当形式填空。
1.Our teacher gave us a lot of__________(help)books on math.
2.Most__________(leaf)on the trees turn yellow in fall.
3.The sick man came to Beijing for better __________ (medicine)treatment.
4.His________(pronounce)has improved,but he still does much practice every day.
5.The policemen that lost their lives in the earthquake are___________(hero)in my heart.