1. He is an ungrateful person who never thanks anyone.
他是一个忘恩负义的人，从不感谢别人。

2. Don't be an ungrateful person after receiving help.
得到帮助后不要做忘恩负义的人。

3. She felt disappointed by her ungrateful son.
她对自己忘恩负义的儿子感到失望。

A: You should appreciate the support you got.
A：你应该感激你得到的帮助。

B: I don't want to feel like an ungrateful person.
B：我不想成为一个忘恩负义的人。

1) 忘恩负义的人

2) 不感激他人帮助的人

3) 带有负面评价的行为描述

1. 不懂得感恩的人

e.g. An ungrateful person often complains even after receiving help.
一个忘恩负义的人即使得到帮助也常常抱怨。

2. 忘记别人的好意的人

e.g. She was called an ungrateful person by her friends.
她被朋友们称为忘恩负义的人。

noun phrase

1. A person who does not show gratitude for help or kindness received.

Synonym: thankless person, inconsiderate person