He is too timid to venture upon an undertaking.是什么意思？

He is too timid to venture upon an undertaking.

他太胆小,不敢从事任何事业。

he

pron. 他，它，一个人；n. 雄性动物；

例句
Logic had prevailed and he had abandoned the idea.
最终理智占了上风，他打消了那个念头。

is

vt.& vi. 是（be的三单形式；n. 存在；

例句
Bollinger 'RD' is a rare, highly prized wine.
博林格RD香槟是一种名贵的备受推崇的葡萄酒。

too

adv. 也，太，很，非常；

例句
The steep pavement was too narrow for them to walk abreast.
陡坡太窄，他们没法并排走。

timid

adj. 胆小的，羞怯的，怕人，羞手羞脚；

例句
A timid child, Isabella had learned obedience at an early age.
伊莎贝拉是一个羞怯的孩子，很小就学会了顺从。

to

prep. 向，朝着，到，关于，属于；adv. 朝一个方向的，到某种状态，关闭；

例句
I suggest you leave it to an expert...
我建议你把它留给专家来解决。

venture

n. 冒险事业，冒险，冒险行动，商业冒险；vt. 冒…的危险，拿…冒险，用…进行投机，以…做赌注；vi. 冒险前进，冒险行事，猜测（常与at连用）；

例句
...an announcement by Steetley and Tarmac of a joint venture that would combine their operations...
斯蒂特利公司和泰玛士集团发表的整合其生产经营成立一个合资企业的声明

upon

prep. 在…上面，当…时候；

例句
...the doctrine of absolute monarchy based upon divine right.
以神权为基础的君主专制学说

an

art. 一（在元音字母前代替不定代词a），一任一某一，一个；

例句
He started eating an apple...
他开始吃苹果。

undertaking

n. 企业，事业，殡仪事业，保证；v. 担任( undertake的现在分词)，着手作；

例句
It promised to be a more difficult undertaking than might appear at first sight...
那项任务可能比乍看之下还要困难。