I was prevented from coming by force of situation.

我为形势所迫而不能来。

He had brought his friends here, almost by force of friendship.

他几乎是靠着友情，把他的朋友领到这里来的。

In America, industry conversion was adjusted by force of market.

美国主要放任不管，依靠市场机制调节。

He improved the quality of work in his department by force of example.

他以身作则带动他那个部门提高了工作质量。

The mother was very neat; her daughter learnt to be neat by force of example.

妈妈很爱整洁，由于榜样的力量，她的女儿也学会爱整洁。