在英语中，频度副词是一种用于描述某个动作或状态发生的频率的副词。常见的频度副词包括always、often、sometimes、rarely和never等。那么，在句子中，频度副词应该放在哪个位置呢？

频度副词的位置

一般来说，频度副词通常放在行为动词之前，如：

I always eat breakfast at 7 o'clock in the morning.

He often goes to the gym after work.

She rarely drinks coffee because it keeps her up at night.

但是，如果句子中有情态动词，频度副词则应该放在情态动词之后，如：

She can never remember where she put her keys.

They should always wear helmets when riding bicycles.

He might sometimes forget to lock the door.

另外，频度副词也可以放在句首或句末，但这样做会强调频度副词所描述的内容，如：

Always remember to say "thank you".

I go to the gym after work, often.

Rarely do I watch TV on weekdays.

频度副词的用法

频度副词通常用于一般现在时态和一般过去时态，表示动作或状态的频率。例如：

She always eats breakfast at 7 o'clock in the morning. (她总是在早上7点吃早餐。)

I rarely go to bed before midnight. (我很少在午夜前上床睡觉。)

They often played basketball when they were in college. (他们在大学时经常打篮球。)

需要注意的是，在一般将来时态中，频度副词通常放在助动词will或be going to之后，如：

We will always love each other. (我们将永远相爱。)

He is going to rarely eat meat from now on. (他从现在开始很少吃肉。)

总之，掌握频度副词的位置和用法可以帮助我们更准确地表达动作或状态的频率，使我们的语言更加丰富和准确。