equipment 和facility 都可译作“设备”，“器材”，但equipment 是不可数名词，指用于某一特殊目的的东西，供给品，装备等。如：
a completer of equipment
an important piece of equipment
basic kitchen equipment
stereo equipment
facility 是可数名词，常用复数形式。facilities指为一特殊活动或目的所提供的种种便利，包括设备、建筑物和服务等等。如：
production facilities
facilities for study
facilities for travel
sports facilities
device
装置,设计,策略,设备
这个既可以是抽象的,也可以是具体的
比如:
1. They use television advertising as a device for stimulating demand.
他们利用电视广告作为刺激需求的方法。
2. Her illness is merely a device to avoid seeing him.
她所谓生病只不过是避免见他的花招而已.
3. The device had undergone extensive testing.
这种装置经受过广泛的试验。
tool
工具
例句与用法:
1. Words are the tools of his trade.
言语是他那一行必不可少的工具。
2. The artist tooled a pattern onto the cover of the book with a hot needle.
那位艺术家用烧热的针在书的封面上烫出图案。
3. This program gives managers a valuable planning tool.
这套程序是经理人员制订计划的可贵的工具。