Should ปกติมีความหมายว่า ควร ควรจะ โดยเป็นการพูดเชิงแนะนำ แต่บางครั้งก็หมายถึงเป็นการชักชวน

Should have = should’ve

ตัวอย่าง
I should have studied.
You should have written to me.
He should have called his father.
We should have listened to the teacher.

Negative
Should not have = shouldn’t have
ตัวอย่าง
I should not have studied.
You should not have written to me.
He shouldn’t have called his father.
We shouldn’t have listened to the teacher.