eat away

1. 侵蚀
   Rust is eating away the iron hinge.

   铁锈正腐蚀着铁铰链。

2. 继续吃；尽情地吃
   They had been eating away for two hours.

   他们已经吃了两个小时，还在吃。

eat into

1. 侵蚀
   The acid eats into metals quickly.

   酸腐蚀金属很快。

2. 逐渐耗尽
   Her extravagance ate into her husband's inheritances.

   她挥霍无度，使她丈夫所得的遗产日益减少。

eat out

1. 上馆子吃饭
   They usually eat out on Sundays.

   星期天他们通常上馆子吃饭。

2. 锈坏；使腐烂
   Rust had eaten out the gun barrel.

   枪筒已被锈蚀。

eat up

1. 吃完；吞噬
   Eat up the dinner while it is still warm.

   趁饭还热，快把它吃完。

2. 消耗；用完
   The work ate up all his time.

   那工作占用了他所有的时间。

• eat one's heart out
  suffer from excessive longing for something unattainable.
• eat like a bird (or a horse)
  informal eat very little (or a lot).
• eat one's words
  retract what one has said, especially in a humiliated way.
• I'll eat my hat
  informal said to indicate that one thinks something is extremely unlikely to happen.
• what's eating you (or him etc.) ?
  informal what is worrying or annoying you?