1.心正不怕雷
A good conscience is a soft pillow.
2.心甘情愿
He did all this of his own accord.
3.心满意足
as happy as a clam.
4.心力交瘁
burn the candle at both ends.
5.心灰意冷
be in black despair (down in the bushes/in the dumps/lose heart)
6.心有余悸
A burned child dreads the fires. (Once bitten, twice shy.)
7.心安理得
have the peace of mind. (have an easy conscience)
8.心血来潮
on the impulse of the moment
9.心花怒放
My heart sings with joy because I receive over 300 letters a week from people around the world.
注：
A. dread：惧怕，恐惧
常用词组：
1) in dread of someone：害怕某人
2)in dread of one's life：害怕有生命危险
B. impulse：冲动，心血来潮
常用词组：
1)impulse buying：即兴购买，未经考虑仅凭一时冲动的购物行为
2) electrical impulse：电脉冲
