（一）许多: [ xǔ duō ]
1. much
2. many
3. a lot of
其它相关解释:
<lac> <lots of> <quite a little> <no little> <not a little> <oodles> <plenty of> <quiverful> <an amount of> <any number of> <scad> <bags of> <lotta> <a great of> <a number of> <a tons of>
例句与用法:
1. 修筑一条铁路要花费许多劳动力。
It takes a lot of labor to build a railway.
2. 我有许多唱片。
I have many discs.
3. 这些年，他干了许多可耻的事情。
He has done many dishonorable things these years
4. 许多疾病是由细菌引起的。
Many diseases are caused by bacteria.
5. 他的成功是由于勤勉和许多朋友的帮助。
He succeeded both because he was industrious and because he had many friends to help him.
6. 我想我们能从中学到许多。
I think we may learn much from it.
7. 那位诗人为她写了许多诗。
The poet has written many poems for her.
8. 因为污染严重，许多美丽的鱼类正在面临绝种。
Many beautiful fish are fast disappearing because of the severe pollution.
（二）大量: [ dà liàng ]
1. numerous
2. great amount
3. large quantity
其它相关解释:
<great deal> <Mass.> <in the gross> <raff> <right smart> <substantial> <slather> <a great lot> <a great deal> <a body of> <a large number of> <a sea of> <like flies> <a great/good deal of> <barrelful> <large amounts of>
例句与用法:
1. 暴风雨造成了大量物质损失。
The storm did a great deal of material damage.
2. 因为气温很高，有大量空调售出。
A large quantity of air-conditioners has been sold since the temperature is high.
3. 这家工厂生产大量的纸制品。
The factory turns out a large quantity of paper products.
4. 他有大量的参考书可供使用。
He has a large number of reference books at his disposal.
5. 每年都要花费大量金钱在广告上。
A large amount of money is spent on advertisements every year.
6. 该系统的主要弱点之一是消耗大量燃料。
One of the main disadvantages of this system is that it uses very large amounts of fuel.
7. 我们为这一项目付出了大量的时间和精力.
We've put a great deal of time and effort into this project.
8. 劳资双方之间存在大量矛盾.
There is a great deal of friction between the management and the work force.
[注]许多和大量自然是一个意思啦，细细品位加以区别吧，再翻翻字典。
参考资料：Dict.CN