Chinese phrase translation: 二把刀 (èr bǎ dāo) amateur

二把刀 (èr bǎ dāo)amateur; smatterer

Usage:

“二把刀”原来是指厨师的副手,后来指技术水平、工作能力不够高或者是对某项知识了解得还不够的人。当这个词用来形容说话人自己时表示自谦，用来形容别人时，有贬义色彩。
"二把刀" originally meant assistant cook. Later, it refers to a person whose skill, ability for work, or knowledge is not enough. You can also hear people say it about themselves to show modesty. If it is used on somebody else, then it carries the derogatory meaning.
Sentences:

1、Tā shì gè èr bǎ dāo sījī, yì chūmén jiù zhuàng zài shù shàng le.
他是个“二把刀”司机，一出门就撞在树上了。
He is not a skilled driver and he hardly drove out of the yard when he crashed into the tree.
2、Tā shuō zìjǐ shì yīgè xīnlǐxué zhuānjiā,qíshí zhǐshì gè ér bǎ dāo.
他说自己是一个心理学专家，其实只是个“二把刀”。
He said that he is a psychologist. Actually, he was only a person with a little psychological knowledge.