英語中有些表示頻率的詞在句子中有著重要的作用，正確理解並應用，可以使我們的表述更加準確，不會產生歧義。
總結起來，英語中有6個常用的表示頻率的詞，我們來看看它們的準確含義。
特別提示一下，為了更好地解釋單詞的含義，我選擇用英文解釋，大家可以認真體會一下。
這6個表示頻率的詞如下：
always usually often sometimes seldom never
我們用百分比來表示一下這幾個詞的關係：
always 100% all of the time
usually 100% most of the time
often 50% much of the time
sometimes 50% some of the time
seldom 0% almost never
never 0% not at any time
從以上可以看出，always和usually的頻率是最高的，其中always幾乎是頻率最高的時候用，而usually次之。
看兩個例子：
My cat always stays in home.=My cat stays in home all of the time.（大多數貓咪都這樣吧）
He usually goes to shopping mall at weekend.=He goes to shopping mall at weekend most of the time.
often和sometimes頻率只有一半，意味著如果你使用這兩個詞，別人會認為你有一半時間可能不是這樣做。
再看兩個例子：
Her sisters often have coffee together.=Her sisters have coffee together much of the time.(That means, they don't have coffee together all of the time.)
The president sometimes goes to bed before eleven.=The president goes to bed before eleven some of the time.(That means, the president doesn't always go to bed before eleven.)
頻率最低的兩個詞是seldom和never，低到詞性都具有否定意義了，如果你用這兩個詞，那就是非常明確且堅定地告訴別人，你從來不會這樣做。
還是看兩個例子：
Mary seldom has dinner with her boyfriend.=Mary almost never has dinner with her boyfriend.（咦，什麼情況？）
Mary will never have dinner with her boyfriend.=Mary won't have dinner with fer friend at any time.（情況比較嚴重哦）
以上幾個表示頻率的詞，有些時候是可以百分比相近的詞是可以混著用的，但有的時候需要更明白確切地表達的時候，就要認真對待了。
You will never forget these words, will you?