英语语法分析

Time and again, Mr. Heaney returns to the image of the pen. He began his long career writing of such a pen, nestling snug as a gun between finger and thumb.

希尼先生一次又一次回到了“笔”这个意象中。他开始了他漫长的写作生涯，这支笔就像一支枪，舒适地依偎在他的手指和拇指之间。

A classic example is noisy begging by nestling songbirds when a parent returns to the nest with food.

一个典型的例子就是鸣禽的雏鸟在父母带着食物归巢时所表现出的吵闹的乞食行为。

Therefore, a begging nestling that secures food at the expense of its siblings might actually leave behind fewer copies of its genes overall than it might otherwise.

因此，一只以其兄弟姐妹为代价来获取食物的乞食雏鸟实际上可能会比其它雏鸟留下更少的基因副本。