He exchanged a piece of gold for its equivalent in silver.

他用一块金子换取了等价物的银子。

You must give them a piece of gold at the end of every day.

你必须在每天的活干完后交给他们一块.

One day he saw a piece of gold on the road and picked it up.

有一天，乐羊子在路上看到一块金子，他就捡起金子，带回了家并把它拿给妻子看。

I only asked if a piece of gold as big as my head was valuable.

“我只问一块和我的头一样大的金子值不值钱. ”

After several dances Ali Baba and his son gave her a piece of gold.

跳了几段舞后,阿里巴巴和他儿子赏给玛琪安娜一块金子.

My experience about CAI is that one will not be satisfied with only a piece of gold but with turning computer into a gold finger which can change stone into gold.

把电脑变成点石成金的金手指而不仅满足于一块金子是我对CAI 的体会。