keep、retain、withhold、reserve都含"坚持"、"保存"的意思。
系常用词, 指"使持续下去""使较长时期地置于不脱离操控、把握、照顾或改变之下", 如:
keep the room clean.
坚持室内清洁。
较正式, 着重"持续坚持", 特指"坚持使不失掉或被夺走", 如:
He has managed to retain most of his fortune.
他设法保存了他的大部分产业。
着重"保存"、"藏匿", 指"阻挠其离去或走漏", 如:
Fear made him withhold the truth.
惊骇使他不敢说实话。
指"为一意图坚持, 或保存一段时间", 如:
A great future is reserved for you.
光亮的出息在等待着你。
forbid、ban、prohibit 都含"制止"的意思。
口气较重, 指威望机关"正式制止", 含"严峻斥责"之意,只能用事务作其宾语, 如:
Ban atomic and nuclear weapons!
制止原子武器和核武器!
指"经过法则或政府法则制止", 如:
The soldiers were prohibited from leaving camp after dark.
天亮后战士禁绝脱离营房。
permit、allow、let 都含"答应"的意思。
permit和 allow 在许多情况下能够通用, 但它较 allow 正式, 含有"积极地、从正面地答应"的含义, 如:
They don’t permit you to smoke.
他们不答应你抽烟。
let是三个词中最不正式的, 较口语化, 而语意最弱, 指"给予或许或赞同", 有时含"难以阻挠或约束"之意, 如:
Let him wait.
让他等一等。