These words say how often, from the most times to the fewest:
always — every time
usually — almost every time
often — many times
sometimes — on some days, not most
rarely — almost never
never — not one time
How often each word means
I always brush my teeth. (every day)
She usually walks to school. (almost every day)
We often eat rice. (many days)
He sometimes plays games. (on some days)
We rarely eat out. (almost never)
They never drink coffee. (not one time)
Not "sometimes = every time" — say "sometimes = on some days, not most". sometimes is in the middle: more than never, less than often.
Try it: Which word means on some days, but not most days? (sometimes / always / never) Answer: sometimes — If you picked always or never, those are the two ends: always is every time and never is not one time. sometimes sits in the middle — some days, not most.
Before the action word
Words like always, usually, often, sometimes, never say how often. Put them before the action word.
She eats breakfast. → She always eats breakfast.
They watch TV. → They never watch TV.
I play tennis. → I sometimes play tennis.
Not "I eat always breakfast." — say "I always eat breakfast.". The frequency word comes before the action word (eat), not after it.
Try it: She wakes up early. Put the words in order. Answer: She usually wakes up early. — The frequency word goes right before the action word: She usually wakes up early. Not "She wakes up usually early."
After am / is / are
But with am, is, are, the word goes after the verb be.
She is late. → She is usually late.
I am happy. → I am always happy.
They are busy. → They are often busy.
Not "She always is late." — say "She is always late.". With is, the frequency word goes after it, not before.
Try it: He is late. Put the words in order. Answer: He is often late. — After the verb be is, the frequency word comes next: He is often late. With am/is/are, the word goes after, not before.
Try it: Before the action word, but after the verb be. Lars ___ tired in the morning. (is always / always is) Answer: is always — "Tired" goes with the verb be is, so the frequency word comes after it: is always tired. (Before action words, but after am/is/are.)