例句：
Their friendship soon deepened into love.
他们的友谊很快发展成为爱情。
Your friendship means a great deal to me.
你的友谊对我来说是很珍贵的。
By degrees their friendship grew into love.
他们的'友谊逐渐发展成为爱情。
A bond of friendship had been forged between them.
他们之间形成了一种友谊的纽带。
